I don't think what SMS app I have on the phone matters. It is the SMS app on the watch. Actually I don't seem to have a SMS app on the watch. I get SMS notifications, but I only see the message from the notification. I can reply to that message in the notification, but I can't see previous messages from that person.
So if someone sends 2 or 3 messages in a row, I only see the last one on the watch. Maybe I am doing something wrong.
I can't figure out how to find a specific Gear 3 app like Yaata or SMSgear and get it on my watch. Searching apps on the gear 3 app on the phone does not find them. I can scrolled through the different categories of apps to download on my phone but I still could not spot them.
Probably was a mistake getting Samsung watch with non Samsung phone. Messaging barely works and taking calls on the watch works, but then i can't take a call on the phone because I can't hear the other person unless I disconnect the phone connection in Bluetooth for the gear 3 watch. Frustrating.
What's happening with the text messages is that the messaging app on the watch only syncs with the native Samsung Messaging app found on Samsung phones. You don't have to use the native app on a Samsung phone as a default, the watch will still sync the two in the background.
So on a non-Samsung phone, all you're really getting on the watch is the
notification from the messaging app on the phone. Essentially the watch will mirror the notification curtain on your phone. Some messaging apps allow you to view more from the notification itself, so that's why you see can see more on the watch when using Textra. But the messages are still not stored on the watch itself like they would if you were using a Samsung phone.
Even with Samsung phones, we see the same behavior when using a messaging app like Google Hangouts or Facebook Messenger. There is no native app for the watch (Tizen OS), so it just gets the notification from the phone which you can reply to, but once the notification is dismissed, there is no way to retrieve any conversations or messages from those apps on the watch.
While the watch does many things, in most cases it's simply a relay for notifications. There isn't true two-way communication between the watch and phones.
As for the calling issue, not sure what's going on there. In this case, the watch should operate no differently than a Bluetooth earpiece or headset. So sorry, I can't help there.