So first time posting, long time lurker: I've been playing around with Foreflight's custom map features and they're really great. I've been able to download all kinds of georeferenced maps, turn them into MbTiles, and load them on my iPad Foreflight app. Really great stuff. Here's where I need some help- I'd like to merge MbTiles together. Specifically, I want to merge USGS maps (both historical and current) into a single large Mbtile that would cover an entire state (South Carolina specifically). The software to do this is really expensive- does anyone already have access for work or school that could help out? I know this is on them fringe of an aviation related topic- but I really like flying with USGS maps as they provide a little extra situational awareness in VFR.