Hi there,
Glad to help… So my device is a BLE based security device for Motion Picture Lenses and Camera Bodies. Took me 3 years to get the Patent. (those are very early PCB’s all MSMD now.)
So the Pads on the Xiao do not present any problem for the right tech. READ the posts about it there are a few. I will be posting shortly a new thing and a New New thing for it. The Seeed engineers used the method to solder this test unit so you see more about that. There is plenty of methods for the battery charging and some have even modified the Xiao which you could probably get seeed to sub in your part on a custom build. Check out there services.
HTH
GL PJ
here is a NON spoiler alert pic of said Soldering tech…on a soon to be commercial product
everyone is gonna want one…for sure.
camera and lens like this…BTW approx value $180k-$260k