I concur with Textra. Though it has some bugs using it with T-Mobile. But there is a setting specifically for T-Mobile and that seems to resolve it. There are still some issues, but the stock app also has the same bugs so I'm assuming those are on their end. I've been using the stock app on my s7 and now my s8 for better gear s3 integration, but it seems I haven't really used any of the features I gain on the watch from using the stock app. I may switch back soon. The stock app on phone is a bit frustrating.