Aptoide a great playstore alternative

Aptoide application is alternative to playstore and it has pro versions of applications,you don't to buy expensive applications anymore
beware there are some virus applications ,so the official Aptoide website is https://www.aptoide.com

I'm not going to tell you not to download paid apps from secondary sources, but just be careful as a they can be very dodgy. For example, many root-based apps can bypass virus detection and the like.

Just a heads up to be careful!