Motivation is an interesting psychological concept. Even if you haven't really read much about it, you probably know when you are motivated, as well as when you are not. For the times when motivation eludes you, when it's hard to achieve anything at all, we've prepared a selection of apps - all for Android - that could be of help. There are 5 apps to check out, each of them free to download via Google Play (download links are included).
Whether or not these apps actually work probably depends on each and every individual that uses them. Anyhow, give them a try if you need to be motivated in whatever it is that you're doing. You may find at least one app that really helps.