If your computer does not start up, the first thing is to check that it is connected to the power supply. When your mouse batteries are low, change them. With a wireless mouse, you need to plug it Into the computer to charge it. You can also charge your phone with a mobile charger. If your apps are running slowly, it may be because of a file that you have downloaded from a website. You need to find out how to delete or remove it. Alternatively, you may need to update the app.