(Pocket-lint) - Fitbit has been developing its very own smartwatch, and has been buying companies such as Pebble to strengthen its team and to ultimately produce a product that consumers will want to buy.

However, according to a Bloomberg report, the smartwatch project is having a tough time after several people working on the project have left, which has affected development of the dedicated app store. Fitbit's smartwatch will run its own operating system, rather than something like Google's Android Wear.

This means it needs its own OS and its own app store and because the Fitbit watch will have formidable competition in the form of the Apple Watch, Samsung Galaxy Gear watches and various other Android Wear watches, coupled with the fact that wearables in general are not as popular as first thought, developers are less keen to produce apps specifically for Fitbit.

Damian Mehers, who developed a version of Evernote for the Galaxy Gear, has been quoted as saying: "I'm more focused on the big boys like the Apple Watch and Android Wear. I could consider developing for Fitbit if there was a compelling device and a large enough user base".

However, Fitbit says the smartwatch project is still on track and the app developer program has been well-received. The upcoming smartwatch is "well positioned to succeed".

Apps for the Fitbit smartwatch will be written in JavaScript, which should in theory make it easy for developers to create apps, but going down the Android Wear route would have immediately given the smartwatch access to a vast store of apps and a large community for support.

The app store may in fact be downloaded to an iOS or Android device, where users can then download apps and send them to the watch via Bluetooth.

Fitbit's smartwatch is expected to adopt a square shape, similar to the Apple Watch, but according to Bloomberg's report, several people inside the company don't believe it will succeed. They consider it substandard to the Apple Watch 2, the product it was initially meant to go up against, but now that its release has been pushed back to at least the fall, it will end up going head-to-head with the Apple Watch 3 instead.

Writing by Max Langridge.