The author doesn't seem to have an open source mobile app or anything that would allow them to source the data from devices themselves. I'm curious where the data was collected from, esp. if it was opt-in (at the collecting device)
The developer might be open to add other services since MLS is being retired: https://github.com/zamojski/TowerCollector/issues/223
Doesn't hurt to contact them/make suggestions on this issue.