I just recently started learning Android and am working on small projects to learn the essentials I need for to work on a larger project I have coming up. I need to get the users last know location. I went through this tutorial, and it wouldn't connect to play services. Do I need an api key to get the last known location? And also what is the easiest way to implement location awareness in Android?
You need not to give any API key to fetch last known Location. API key is needed when integrating Google Maps in Android app. Android Location API using Google Play Services
No you don't need api key for last known loacation. You should follow these tutorial of android provided by google. Very easy and efficient Link
来源：https://stackoverflow.com/questions/35033410/do-i-need-an-api-key-to-get-last-known-location-in-android-with-google-play-serv