This app was mentioned in 2 comments, with an average of 1.00 upvote
There is an android port of QGIS still labelled experimental, and basically the full desktop app rather than a mobile app.
What is igis?
https://play.google.com/store/apps/details?id=org.qgis.qgis&hl=en
This looks interesting! I think it should be mentioned that QGIS has an experimental Android port.