Imagine there was a version of the Apple Watch that could go for four or five days between charges and work with Android phones as well as iPhones. The catch is that this superlative waterproof fitness tracker -- with sleep tracking!

The Fitbit Ionic offers a comfortable design, with 50-meter water resistance for swimming, GPS and mobile payments; You only need to recharge it once or twice a week

While the Ionic supports future apps and watch faces, few are available yet; Included apps feel slow and don't launch from the watch face; There's not much on-watch coaching and music storage and playback is often more trouble than it's worth

If the Apple Watch is a smartwatch first and a fitness tracker second, the Fitbit Ionic feels like the inverse. Depending on what you're looking for in a wearable, that could be a very good thing. The Ionic's $300 price tag places it firmly in Apple Watch territory.

Vibrant screen; Changeable straps; Safe for swimming; Excellent battery life; Smart notifications; Built-in GPS and NFC; Pandora integration; Open SDK for app developers

Expensive; Thick bottom bezel; Case easily scratches

Ultimately, the Ionic is a respectable debut for Fitbit's first serious attempt at a true smartwatch, and the company continues to excel at fitness-tracking features. But while its new operating system is intuitive and well-designed, overall the device still feels like a placeholder.

Bright display; Long battery life; Comprehensive fitness features; Swim tracking; Contactless payments work well

Finicky; incomplete software; Cannot reply to notifications; Limited selection of third-party apps

Fitbit is probably the most well-known company in the fitness tracker world, but smartwatches are new territory. The closest they've come to making a smartwatch was 2015's Fitbit Blaze , but even that wasn't all that smart.

Interchangeable straps make it great for the office and gym Touchscreen is easy to read outdoors Great overall fitness tracker Sleep tracking is detailed and helpful 2.5 GB of storage for music 5 ATM water resistance Fitbit mobile app is intuitive and user friendly Fitbit Pay works flawlessly...

Design is clunky Can't interact with notifications Fitbit OS is laggy

The Ionic is Fitbit's latest smart device release and it includes all the features you'd expect with a fitness tracker like GPS, a heart rate monitor called PUREPULSE®, and sleep tracking. Additionally, there is onboard storage for 300+ songs and downloaded Pandora playlists.

At this stage it's hard to specifically recommend the Ionic. Not so much because of its hardware or interface problems, such as music sync, but because third-party support just isn't there yet. To compete with Apple, the product needs smarthome apps. Messaging apps. Ridesharing apps.

Fitbit is off to a great smartwatch start with their Ionic... even though it's more fitness than smartwatch!

Fitbit Ionic review: This is the first smartwatch from the company and aims to woo customers who want to add a layer of smartness to their fitness regime.

If you're more focused on fitness, Garmin's Vivoactive 3 lasted about three days on a charge during my tests. With a round face, Garmin's new smartwatch is more fashionable than the bulky, square Ionic.

For the past year it looks like Fitbit has been trying to be more active in the fitness tracker space even though they practically own it. There has been buzz from competitors here and there, but they seem to have it on lock.