I would recommend using a computer for that sort of thing.
Now, that said, if you do go the PC route then you might as well nab DaVinci Resolve and lurn u up some proper video editing along the way. It's 1: free, and 2: in principle able to do virtually any video-related thing you've ever even heard of.. and at least twice as many you never even knew existed. :P
The primary drawbacks would be 1: "whah I can't do this from my fitbit" and 2, the more legitimate concern "all I really want to do is overdub and I will have to watch a youtube video or two on how this all works to do that here".
The only app-based solution I can think of is TikTok. Yeah, I didn't think you were interested in abridging quite THAT far, either. xD
Hi, here is a free android app for creating custom soundboard using sounds from audio or video files from your device storage.
https://play.google.com/store/apps/details?id=com.gyokovsolutions.soundsamplerlite
There are different types of buttons for different playing options (loop, stop on release etc...) and you can control sound volume and balance for each button. Also file cropping and fade in/out is possible.
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App features:
- set custom sound files from your device (audio or video) for button
- use different types of play (loop, start/stop on press/release etc...)
- adjust individual sound volume and balance
- use file cropping for sound
- fade in/out for sound
Check full version for more features.
I know it's not quite what you are looking for but there is an app called Walli. You can set it to change the wallpaper for home, lock or both screens and will only change after a set amount of time, you choose. The only downside is there is no way to get your own images on there but there is a wide variety of images on there that are all high quality.
https://play.google.com/store/apps/details?id=com.shanga.walli