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Apple Watch Series 5 vs. Fitbit Ionic – Smartwatch Comparison


The Fitbit Ionic, despite its age, is still one of the best smartwatches to buy. It offers a complete experience that still fares better compared to budget smartwatches today. This is largely thanks to Fitbit’s expertise in the health and fitness tracking industry.
The Apple Watch, on the other hand, is easily one of the most popular smartwatches in today’s market. Despite being exclusively made for consumers within the Apple ecosystem, it has become one of Apple’s most successful products in its current lineup. 
If you are shopping for a new smartwatch, you might be thinking. Is the Fitbit Ionic enough to bring a satisfying experience? Or is it worth adding more to obtain the Apple Watch Series 5’s more refined user experience and more premium build quality? Keep on scrolling to find out. 

Apple Brand Overview

Apple Watch Series 5 (GPS, 44mm) - Gold Aluminum Case with Pink Sport Band
Apple Watch Series 5 (Image: Amazon)

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Apple is easily one of the most iconic names in the world of technology. This company has been responsible for some of the most recognizable products in the industry. They were responsible for the Macintosh, iPod, iPhone, AirPods, etc. 
And if there is one word to describe this company, it would be innovation. The iPhone single-handedly changed the name of the game. That one single product transformed smartphones from pocket telephones to multimedia devices. It even arguably changed the way we live our lives. 
That kind of revolution can be seen in nearly all of their products. And that also applies to the Apple Watch. This relatively simple product has transformed wristwatches into extensions of our smartphones and can do things beyond what was imaginable at the time. 
It has since then been copied nearly countless times by its competitors. However, many still regard it to be the industry standard in smartwatches. Keep on scrolling to find out how well it fares against the Fitbit Ionic. 

Fitbit Brand Overview

Fitbit Ionic GPS Smart Watch, Charcoal/Smoke Gray, One Size (S and L Bands Included)
Fitbit Ionic (Image: Amazon)

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🏆 #1 Best Overall
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LIVIKEY Fitness Tracker Watch with Heart Rate Monitor, Activity Tracker with Pedometer, Sleep Monitor, Calories & Step Counter, IP68 Waterproof Smart Watches for Women Men Fitness Watch for Sports
  • Heart Rate and Sleep Monitoring: The Fitness Tracker monitors your heart rate automatically all day, and you can select manual mode through the App. The fitness Watch also monitors your sleep at night, providing a detailed analysis of your sleep quality (deep sleep, light sleep, awake time). It is a health advisor for women men in daily life.
  • Multi Sport Modes with Activity Tracking: The fitness tracker features 9 sport modes like running, walking and more. Additionally, the activity tracker records daily steps, calories burned, walking distance and active time throughout the day. You can also set a daily steps goals through the App to track your progress.
  • Smart Notification Reminder: You can get SMS messages, and SNS notifications directly on your wrist including Facebook, Twitter, Gmail ect. You won't miss any important calls and message and stay updated. Please note: the smart watch can not make calls or text.
  • Long Battery Life and IP68 Waterproof: This smart watch only requires 2 hours of charging and can be used for 5-7 days continuously. IP68 waterproof rating can withstand daily sweat, washing hands and rainy day, allowing you to fully enjoy your workouts.
  • More Functions & Compatibility: Fitness watch comes with multiple smart functions such as stopwatch, alarm clock, breathing guide and sedentary alert, enhancing convenience to your daily routine. The tracker is compatible with iPhone Android Phones which run on iOS 8.0 or Android OS 4.0 & Bluetooth 4.0 or above. Please note that it is not compatible with tablets or computers.

Fitbit is an American fitness and health brand founded in 2007. With their innovative health-focused products, Fitbit spearheaded its way to the top of the wearable competition. 
Fitbit’s smartwatches offer similar features to high-end alternatives such as the Apple Watch and the various Wear OS watches. But one edge that they have over their competitors is their background in health and fitness. With their watches, they can bring innovative ideas that help improve the lives of its users. 
Overall, Fitbit is a serious competitor in the smartwatch market. Keep on scrolling to find out how well one of their earlier models, the Iconic, fares against the newer Apple Watch Series 5. 

Specs Apple Watch Series 5 vs. Fitbit Ionic

 

  Apple Watch Series 5 (GPS, 44mm) - Gold Aluminum Case with Pink Sport Band Fitbit Ionic GPS Smart Watch, Charcoal/Smoke Gray, One Size (S and L Bands Included)
Brand Apple Fitbit
Model Watch Series 5 Ionic
Screen Size 1.78” (4.52 cm) LTPO OLED Display 1.42”(3.56 cm) Display
Screen Protection Sapphire crystal glass and ceramic back Corning Gorilla Glass, v3
Screen Resolution 448 x 368 pixels 348 x 250 pixels
Pixel Density Sharpness 326 PPI 306 PPI
Touch Type Multi-touch Multi-touch
Watch Dimensions 44 x 38 x 10.7 mm 38 x 45 x 12 mm
Weight 47.8 grams 30 grams
Watch Case Material Aluminum, Stainless steel, Ceramic, Titanium Aerospace-grade aluminum
Bezel Material Bezel-free Aluminum
Watch Design Rectangular, Curved Dial Design Rectangular, Flat Dial Design
Strap Size 22mm
24mm
140 – 180 mm (small)
180 – 220 mm (large)
Watch Colors Black, Pink, Silver, Black, Gold Blue Gray, Slate Blue, Charcoal
Water Resistance Waterproof (5ATM) Waterproof(5ATM)
Swim-proof Yes, recommended Yes, recommended
NFC Supported Supported
GPS With GLONASS, GALILEO, QZSS With GLONASS
Connectivity -Wifi 802.11b/g/n 2.4GHz
-Bluetooth v5.0, A2DP, BLE
-WiFi antenna (802.11 b/g/n)
-Bluetooth 4.0 Low Energy (Syncing range: Up to 6.1 meters (20 feet))
SENSORS
     Accelerometer
Yes Yes
    Heart Rate Yes Yes
    Compass Yes Yes
    Gyroscope Yes Yes
    Barometer Yes No
    Altimeter Yes Yes
    Blood Ox Yes Yes(SPO2)
    Elevation  Yes Yes
    Ambient Light Yes Yes
    Cadence Yes No
FITNESS TRACKING
     Sleep Tracking
   
    Steps Yes Yes
    Floors Climbed Yes Yes
    Heart Rate Monitoring Yes Yes
    Calories Yes Yes
    Distance Yes Yes
    Stress Yes Yes
    VO2 Max. Yes Yes
    Blood Oxygen Yes Yes
    Blood Pressure No No
    Menstrual Cycle Tracking Yes Yes
    Swim Tracking Yes No
    Underwater Heart Rate   
          Tracking
Yes No
    On-screen workout modes Yes Yes 
    Triathlon Mode Yes No
    ECG Tracking Yes No
    Preloaded sport modes Yes Yes
    Safety Tracking Yes No
Battery Life Up to 18 hours
All-day battery life 
Without GPS Mode- 4 daysWith GPS Mode- 10 hours
Battery Technology Li-Ion Lithium-Polymer
Charging Time About 2 Hours 1-2 Hours
Charging Type Apple Watch Magnetic Charger/Wireless Charger USB based charging dock
Compatible OS iOS 13 or later
MAC Os
Android v4.4+
iOS
Windows 10 PC
NOTIFICATIONS
     Email alert
Yes Yes
    SMS alert Yes Yes
    Calls alert Yes Yes
    Event reminder Yes Yes
    Weather Yes Yes
    Third-party apps Yes Yes
     
MEDIA
     Audio
MP3/MP4 MP3/MP4
    Music Streaming Yes Yes
    Bluetooth music Yes Yes
    Radio No No
    Loudspeaker Yes No
    Microphone Yes No
CLOCK FEATURES       
     Time/Date
Yes Yes
    Stopwatch Yes Yes
    Alarm Yes Yes
OTHER FUNCTIONS
     Control camera
Yes No
    Music control Yes Yes
    Find phone Yes Yes
    Text response Yes(iOS) Yes(Android Only)
    Answer call Yes No
MISC
     Payment system
Apple Pay Fitbit Pay
    Companion app Apple Watch Companion” app Fitbit App
    Customizable watch face Yes Yes
    Interchangeable band Yes, 22mm and 24mm Yes
    Voice command Yes(SIRI) No
Internal Storage 32GB 2.5 GB Available 
Operating system WatchOS 6.0 Fitbit OS

Design and Build Quality

Design Language   

Both smartwatches feature a square display that deviates from the usual wristwatch look. However, Apple arguably executes this square design better with its cleaner design. The Fitbit Ionic feels like an older smartwatch design that may not sit well with modern smartwatches. 
The Apple Watch Series 5 has an elegant and premium design. It doesn’t deviate too much from the Apple Watch formula, which is now iconic at this point. In fact, there aren’t too many noticeable changes from the older Apple Watch Series 4
As with most of Apple’s smartwatches, the Series 5 comes in two versions. These are the 44 mm and the 40 mm version. This is always great since you will be able to choose which version fits you best. The only difference between the two is the smaller display and smaller battery on the 40 mm version. 
The Apple Watch Series 5 also comes in aluminum, stainless steel, ceramic, and titanium. It also comes in several finishes such as space gray, gold, silver, and black. 
The Fitbit Ionic, on the other hand, is Fitbit’s entry to the fitness smartwatch market. It also serves as the follow up to the Fitbit Blaze. Its fitness focus is evident with its real-time guidance feature, which is effective for setting workout goals.
In terms of aesthetics, the Ionic is going for a futuristic look inspired by space exploration vehicles. It may look out of place and may not fit everyone’s tastes, considering the minimalist options available in the market. 
This futuristic look has a rectangular shape with sharp edges. The Fitbit Ionic’s strap is made of a flexible and durable elastomer material.   
One design element that Fitbit has done with the ionic is plastic and metal in its casing. This allows more accuracy in its sensors and antennas while maintaining its solid build quality. 
The Fitbit Ionic design, the only real issue with the Ionic is the aesthetic. The large rectangular face and stiff rubber wristband.  But this design makes the watch more angular and feels more durable.  
It also has one button for navigation of the app, on or off, or for emergency phone calls.  On the other hand, the Ionic has three physical buttons for navigation of the watch.  
Both watches have customizable watch faces and interchangeable bands.  

Rank #2
Smart Watch with Alexa Built-in, 1.83" HD Touchscreen Fitness Tracker with Bluetooth Calling, Fitness Watch with Heart Rate/Sleep Monitor, 120+ Sports Modes, IP68 Waterproof Smartwatch for Android iOS
  • Bluetooth 5.3 Call and Message Notification: Cillso smart watch features an advanced single-chip processor and sensitive microphone, enabling direct call making and answering. When you enable the "VeryFit" App to receive messages, notifications will be displayed on the smartwatch. Get all your messages and notifications (Facebook, Twitter, WhatsApp, Instagram, Messenger, Linkedin,Skype etc.) sent straight to your smartwatch with intuitive customizable vibrations
  • Built-in Alexa Voice Control: This smartwatch integrates Amazon Alexa's intelligent voice assistant, delivering a comprehensive hands-free experience directly from your wrist. Simply speak commands to instantly access news, weather, and calendar updates, set reminders, control smart home devices, and manage music playback. This full suite of voice-activated functionalities streamlines daily routines, enhances multitasking efficiency, and keeps your hands free for the moments that matter most.
  • 1.83" HD Display and Personalized Customization: IDW26 smart watches for women men feature a 1.83-inch HDdisplay paired with 3D tempered glass, boasting a resolution of up to 320×385 for excellent image quality and high touch sensitivity. The 4-level adjustable brightness ensures clear visibility even under bright sunlight. Through the "VeryFit" app, users gain access to over 130 stylish watch faces and the ability to create custom designs, allowing for personalized expression
  • 120+ Sport Modes and IP68 Waterproof: Fitness tracker supports 120+ professional sport modes, covering diverse indoor/outdoor activities like running, cycling, and soccer to suit all fitness levels. Equipped with high-precision sensors, fitness watch accurately tracks steps, distance, calories burned, and workout duration to help analyze performance and optimize training plans. With an IP68 rating, it's resistant to sweat, rain, and handwashing (Not for swimming or hot showers)
  • All-Day Health Monitoring: Android smart watch is equipped with a high-precision optical sensor that supports 24h real-time heart rate monitoring, helping you stay informed about your physical condition. It also intelligently analyzes sleep quality, accurately identifying deep sleep, light sleep, and awake phases to help improve your sleep habits. Paired with its dedicated app, you can view long-term health trends and receive personalized insights to gradually develop a healthier lifestyle

Weight and Dimensions 

The Apple watch series 5 (44 mm version) has a dimension of 44 x 38 x 10.7 mm and weighs 47.8 grams, while the Fitbit Ionic has a dimension of 38 x 45 x 12 mm and only weighs 30 grams. Both smartwatches are lightweight and should not cause any issues or discomfort to the user. 

Screen Quality 

Apple Watch Series 5 (GPS, 44mm) - Gold Aluminum Case with Pink Sport Band
Apple Watch Series 5 Screen (Image: Amazon)

As for their displays, the Series 5 has a display size of 1.78 inches. This watch has a screen resolution of 448 x 368 pixels with a pixel density of 326 PPI. The screen is protected by sapphire crystal.  
The Apple Watch Series 5 has one of the best display qualities in the market. The screen is vibrant and has good viewing angles. It will allow you to see the display, no matter the lighting condition. 
Additionally, the Series 5 is utilizing LTPO technology for its Always On Display (AOD). We will talk more about this in the “Features” section. 
The Fitbit Ionic, on the other hand, has a 1.42” display with a screen resolution of 348 x 250 pixels and a pixel density of 306 PPI. The display is protected with Corning Gorilla Glass V3.
The Ionic’s LCD display still holds up despite being several years old. However, it is no match to the Apple Watch’s modern OLED display, which is more vibrant and clear than the Ionic’s display. 
Fitbit Ionic GPS Smart Watch, Charcoal/Smoke Gray, One Size (S and L Bands Included)
Fitbit Ionic Display Quality (Image: Amazon)

Additionally, the Apple Watch has an additional feature called Force Touch, similar to the one implemented on iPhones. Essentially, it gives additional inputs to the watch without resorting to adding more buttons. The Fitbit Ionic does not have a similar feature. 
Both watches have an always-on display feature. However, the implementation of the Apple Watch is noticeably better. 
Overall, both displays are great. However, the Apple Watch Series 5 is easily superior to the Fitbit Ionic. 

Build Quality 

Both smartwatches are dust-proof and water-resistant up to 5ATM. Both watches are also swim-proof and sweat-resistant. You can confidently use both of them for sports and other outdoor activities. The square design of both smartwatches also means that they won’t get in the way while doing your workouts.  
Overall, both smartwatches are well built. But of course, the Apple Watch Series 5 has the edge since it is newer and comes in different materials. And also, the Apple Watch has gone through different revisions, which allowed them to iron out any issues that the previous generation had. 

Rank #3
Smart Watch Fitness Tracker with 24/7 Heart Rate, Blood Oxygen Blood Pressure Monitor Sleep Tracker 120 Sports Modes Activity Trackers Step Calorie Counter IP68 Waterproof for Andriod iPhone Women Men
  • 【Superb Visual Experience & Effortless Operation】Diving into the latest 1.58'' ultra high resolution display technology, every interaction on the fitness watch is a visual delight with vibrant colors and crisp clarity. Its always on display clock makes the time conveniently visible. Experience convenience like never before with the intuitive full touch controls and the side button, switch between apps, and customize settings with seamless precision.
  • 【Comprehensive 24/7 Health Monitoring】The fitness watches for women and men packs 24/7 heart rate, 24/7 blood pressure and blood oxygen monitors. You could check those real-time health metrics anytime, anywhere on your wrist and view the data record in the App. The heart rate monitor watch also tracks different sleep stages for light and deep sleep,and the time when you wake up, helps you to get a better understanding of your sleep quality.
  • 【120+ exercise modes & All-Day Activity Tracking】There are more than 120 exercise modes available in the activity trackers and smartwatches, covering almost all daily sports activities you can imagine, gives you new ways to train and advanced metrics for more information about your workout performance. The all-day activity tracking feature monitors your steps, distance, and calories burned all the day, so you can see how much progress you've made towards your fitness goals.
  • 【Messages & Incoming Calls Notification】With this smart watch fitness trackers for iPhone and android phones, you can receive notifications for incoming calls and read messages directly from your wrist without taking out your phone. Never miss a beat, stay in touch with loved ones, and stay informed of important updates wherever you are.
  • 【Essential Assistant for Daily Life】The fitness watches for women and men provide you with more features including drinking water and sedentary reminder, women's menstrual period reminder, breath training, real-time weather display, remote camera shooting, music control,timer, stopwatch, finding phone, alarm clock, making it a considerate life assistant. With the GPS connectivity, you could get a map of your workout route in the app for outdoor activity by connecting to your phone GPS.

Features

Fitbit Ionic GPS Smart Watch, Charcoal/Smoke Gray, One Size (S and L Bands Included)
Fitbit Ionic GPS (Image: Amazon)

Both smartwatches are feature-packed and cover most of the basic features that most smartwatches have. Here are some highlights for each watch. 

Smart Notifications 

Both watches have smart notifications. Both can receive emails, text, calls, weather forecasts, calendar reminders, and more. However, the Apple Watch Series 5’s implementations are noticeably better due to its more refined software.  
The Fitbit Ionic can show basic notifications, but it cannot interact with most of them. The Apple Watch Series 5, on the other hand, can respond to text messages and answer calls. It is worth noting that the Apple Watch Series 5 is faster and more reliable when it comes to notifications. 

Voice Commands

Additionally, Apple Watch Series 5 has voice commands through SIRI and has a built-in camera remote control function. The Apple Watch also allows you to make FaceTime audio calls to your contacts when connected to cellular data or WiFi via the Phone app. It does not, however,  support FaceTime video calls. 
The Fitbit Ionic cannot do any of these as it lacks a microphone and speaker. 

Rank #4
Smart Watch with Alexa Built-in, 1.83" HD Touchscreen Fitness Tracker with Bluetooth Calling, Fitness Watch with Heart Rate/Sleep Monitor/120+ Sports, IP68 Waterproof Smartwatch for Android iOS, Gray
  • Bluetooth 5.3 Call and Message Notification: Cillso smart watch features an advanced single-chip processor and sensitive microphone, enabling direct call making and answering. When you enable the "VeryFit" App to receive messages, notifications will be displayed on the smartwatch. Get all your messages and notifications (Facebook, Twitter, WhatsApp, Instagram, Messenger, Linkedin,Skype etc.) sent straight to your smartwatch with intuitive customizable vibrations
  • Built-in Alexa Voice Control: This smartwatch integrates Amazon Alexa's intelligent voice assistant, delivering a comprehensive hands-free experience directly from your wrist. Simply speak commands to instantly access news, weather, and calendar updates, set reminders, control smart home devices, and manage music playback. This full suite of voice-activated functionalities streamlines daily routines, enhances multitasking efficiency, and keeps your hands free for the moments that matter most.
  • 1.83" HD Display and Personalized Customization: IDW26 smart watches for women men feature a 1.83-inch HDdisplay paired with 3D tempered glass, boasting a resolution of up to 320×385 for excellent image quality and high touch sensitivity. The 4-level adjustable brightness ensures clear visibility even under bright sunlight. Through the "VeryFit" app, users gain access to over 130 stylish watch faces and the ability to create custom designs, allowing for personalized expression
  • 120+ Sport Modes and IP68 Waterproof: Fitness tracker supports 120+ professional sport modes, covering diverse indoor/outdoor activities like running, cycling, and soccer to suit all fitness levels. Equipped with high-precision sensors, fitness watch accurately tracks steps, distance, calories burned, and workout duration to help analyze performance and optimize training plans. With an IP68 rating, it's resistant to sweat, rain, and handwashing (Not for swimming or hot showers)
  • All-Day Health Monitoring: Android smart watch is equipped with a high-precision optical sensor that supports 24h real-time heart rate monitoring, helping you stay informed about your physical condition. It also intelligently analyzes sleep quality, accurately identifying deep sleep, light sleep, and awake phases to help improve your sleep habits. Paired with its dedicated app, you can view long-term health trends and receive personalized insights to gradually develop a healthier lifestyle

Music Playback 

Both watches can store and play MP3 and MP4 files. They can also stream music through Wi-Fi and Bluetooth.  
In terms of music streaming, you have Apple Music and a dedicated podcast app installed by default on the Apple Watch Series 5. You can also install third-party streaming apps such as Spotify.  
The Fitbit Ionic, on the other hand, is more limited. You can only stream music through Deezer and Pandora. And also, you cannot install third-party apps such as Spotify and Apple Music. 

Sensors 

In terms of the sensors, both watches have GPS and GLONASS onboard. They also have a built-in heart rate sensor. Additionally, the Apple Watch Series 5 has GALILEO and QZSS. Apple Watch 5 GPS is very reliable, even without the apple watch, and has a very accurate heart rate sensor.  
The Apple Watch Series 5 still incorporates most of the Series 4’s sensors. These include the Accelerometer sensor, Gyroscope sensor, Heart rate sensor (2nd Gen), Barometer, Ambient Light sensor, Cadence, and Compass.  
The Fitbit Ionic also has most of the sensors found on the Apple Watch Series 5. However, it does not have a Barometer and a Cadence sensor.  Both watches have a blood oxygenation sensor to estimate your blood oxygen saturation (SpO2) while you sleep. Both watches do not have a temperature sensor, 3D compass, and do not monitor perspiration. 

Other Features  

Both watches have a “Find My Phone” feature that can come in handy if you misplace your smartphone. They also have a silent alarm, stopwatch, vibrating alerts, inactivity alerts, and fitness achievements. 
Additionally, both smartwatches have features designed for women. These include exercises tailored specifically for women. There is also a menstrual cycle monitoring feature that allows the watches to give notifications and alerts to the user when the specified/predicted date is near. 
There is one notable feature that is currently only available in Apple Watches. This is the fall detection feature. This allows the watch to make emergency calls when it detects the user is falling from a certain height. This is a crucial feature to have, especially when you are traveling or hiking alone. 

💰 Best Value
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Apple Watch SE 3 [GPS 40mm] Smartwatch with Starlight Aluminum Case with Starlight Sport Band - S/M. Fitness and Sleep Trackers, Heart Rate Monitor, Always-On Display, Water Resistant
  • HEALTH ESSENTIALS — Temperature sensing enables richer insights in the Vitals app* and retrospective ovulation estimates.* You’ll also get a daily sleep score, sleep apnea notifications,* and be alerted if you have a high or low heart rate or an irregular rhythm.*
  • GREAT BATTERY LIFE — Enjoy all-day, 18-hour battery life. Then charge up to twice as fast as SE 2* and get up to 8 hours of battery in just 15 minutes.*
  • ALWAYS-ON DISPLAY — Now you can read the time and see the watch face without raising your wrist to wake the display.
  • A GREAT FITNESS PARTNER — SE 3 gives you a healthy number of ways to track your workouts. With real-time metrics and Workout Buddy powered by Apple Intelligence from your nearby iPhone,* you’ll hit your goals like never before.
  • STAY CONNECTED — Send a text, take a call, listen to music and podcasts, use Siri, and get notifications. SE 3 (GPS) works with your iPhone or Wi-Fi to keep you connected.

Fitness Tracker

The Apple  Watch  Series 5 can track distance-related activities, steps, and sleep in terms of its fitness tracking capabilities. It can also measure the pace and calories burned. Additionally, it automatically detects activities and will constantly provide activity reports. 
The Fitbit Ionic, on the other hand, can also track sleep, steps, floors climbed, heart rate, calories, distance, stress, VO2 max, and menstrual cycle.  Additionally, it also provides activity reports and sleep reports. Additionally, both watches detect activities automatically, track elevation, have a multi-sport mode, have exercise tagging, and have a stroke counter swimming.  
The Apple Watch also has an ECG tracking, under-water heart rate tracking, and safety tracking, which the Fitbit Ionic doesn’t. Both watches are also compatible with external heart rate monitors.  It supports third-party heart rate monitors to incorporate your pulse data.

Connectivity

Both watches can connect to smartphones via Bluetooth. However, one thing that you have to take note of is that the Apple Watch Series 5 is only compatible with iOS devices. There are no workarounds for the Apple Watch to work on Android devices. 
Additionally, both watches support Wi-Fi and NFC. However, the Fitbit Ionic’s Wi-Fi capabilities are more limited compared to the Apple Watch. Lastly, the Apple Watch Series 5 supports cellular while the Fitbit Ionic does not. 

Battery Life 

The Battery life of the Apple Watch 5 lasts up to 18 hours. It can last throughout a regular day. However, you will surely need to recharge the watch every night. 
The Fitbit Ionic’s battery life, on the other hand, lasts up to five days with mixed usage. And with a GPS mode, it lasts up to 10 hours.

Winner 

Apple Watch Series 5 

Apple Watch Series 5 (GPS, 44mm) - Gold Aluminum Case with Pink Sport Band
Apple Watch Series 5 (Amazon)

Overall, the Apple Watch Series 5 is the clear winner. The Fitbit Ionic still puts up a good fight, especially considering its age. However, the Apple Watch Series 5 has more features and can do everything the Fitbit Ionic does better. 
If you are on a tight budget but still want a great performing fitness-focused smartwatch, then the Fitbit Ionic is still a great choice. However, if you want the best smartwatch experience, then the Apple Watch Series 5 is still the king of modern smartwatches.