You are a miner and you need to explore surrounding landscapes to find items. Tap to move and click on desired square in order to digg.
Be aware to not remain under the ground. Anyway, you can search for items in your inventory and use support, ladder, short lift, long lift, perform seismic analysis, use survival kit or rescue service. You can reveal the entire map if you find the right items underground.
At the general Store you can buy useful items and kits that will help you to explore and survive easily.