Does anyone face a problem of finding a great idea in order to practise some new concepts and technologies?

I always struggle a problem of finding a new idea to develop an application to practise new concepts and enhance my skills in new technologies. Everytime I look for something new to do and get a great app the motivation decreases by the time and I said there is an existant application. What is the new thing that I will add into my app!! Thus, I gave up and I didn't continue it. What are your solutions or suggestions for this issue?