On occasions I develop for the Gear S2/S3 watches from Samsung. (From a development perspective these watches are nearly identical, so I will collectively refer to them as the Gear S watches). When returning to develop after a period away from them there are a few mistakes that I find I sometimes make. Looking in some support forums I see there are others that make these mistakes too. To both help out others that run into this (and as a note to myself) I've made this post to cover some of the checks necessary.
- Ensure Debugging is Enabled
- Ensure Wifi is Always Enabled
- Check the watch's IP address
- Ensure the watch is unlocked
- Connect to the watch from SDB
- Redeploy the development certificate
Ensure Debugging is Enabled
Before anything else will work debugging must be enabled on the watch. This setting will be cleared if you've done a hard reset on the watch or if you have connected it to a different phone. You can change the setting by navigating to Settings ➜ Gear Info ➜ Debugging and ensure that the setting is checked.
Ensure WiFi is always enabled
You'll want to have WiFi set to always on. If you have it set to "Auto" you might not be able to connect. If it is set to "Off" then you will invariably will not be able to connect. Setting WiFi to "Always On" will cause the battery to drain excessively. When developing you'll want to have the charging cradle close by. To set WiFi to always be on navigate to Settings ➜ Connections ➜ WiFi ➜WiFi and select "Always On."
Check the Watch's IP Address
You need to know the watch's IP address to attach to it for debugging and deployment. Remember that the IP address will be different if you go to a different wireless network or could be different if you reconnect to the same network. To see the watch's IP address navigate to Settings ➜ Connections ➜ Wi-Fi ➜ Wi-Fi networks ➜ select your network ➜ scroll down to the IP address.
Ensure the Watch is Unlocked
The watch must be unlocked for the initial connection. While this may be obvious what is less obvious is how quickly the watch can become locked again. The heart rate monitor on the back of the watch also acts as a presence detection sensor; the watch is aware of when it's been removed from your wrist and will go into a locked state almost immediately if you have a lock code/patter on it. When handling the watch if your finger passes over this sensor the watch may lock. You could unlock the watch, set it down in the cradle, and it could be locked again because of your finger coming close to the sensor.
Heart Rate Monitor on the back of the Gear S2
Connect to the Watch using SDB
Before opening Tizen Studioconnect to the watch using SDB. From the command line on your computer (or Terminal if you are on a Mac) navigate to the folder that contains Tizen Studio and then into the tools folder inside of it. Type the following substituting your own IP address here.
sdb connect 192.168.1.181
If this is the first time the watch has connected to the machine from which you are typing the command the watch will prompt you to accept an RSA key. If you don't accept it the connection attempt will fail. Sometimes when you attempt to connect the command line tool will print a failure message the first time even though it has actually connected. Run the command a second time and you'll get a message that the watch is already connected.
Redeploy your Development Certificate
You only need to do this if the watch has been reset since the last time you've done development on it (or if you've never developed on the watch before). Certificate management is a topic of it's own; I won't go into it here. Provided that you have a handle on development certificates the above should be enough to get your watch connected to your computer for development.