If you need any resources for anything in mobile speedrunning (audio, video, timing), join the mobile speedrunning Discord! We can help you out! We also host competitions and share fun mobile games. https://discord.gg/bpY8zeB
On Samsung S7, I use the native recording app, Game Screen Recorder, or DU Recorder to record my games. Each has its perks. For the timer, I use a simple app called Floating Speedrun Timer. It can get in the way of your playing, so make sure its in a good spot before you start recording.
On Amazon Kindle, I use SmartPixel to record, upload to Facebook, download, and add a timer in a video editing software called ShotCut. I'm not sure if this specific game is on that device, though.
If you have a different way of recording and timing, please share!