With networks throttling our data more and more it's become crucial that we don't go over our data limits so we don't incur absurdly high costs. Using WiFi is the best way to limit your data usage but always stay connected to the internet.
Free Zone WiFi for Android is a great app which lets you find free WiFi hotspots in your vicinity or in a desired place. It's great for searching for a hotspot right away or looking for a place where you can go and sit for a while, working away.
The app is completely free and obviously will work better in major cities and towns.