The best app on the market right now. You have 2 options to choose from:
1.) The free version on Krita's official website, which includes everything that the "paid version" does.
2.) Buy it on Steam.

Krita is open source, so you can edit what you want and when you want. Krita is a FREE app, the only reason to buy it on Steam is for developer support or the convenience of updates. It is also possible to send a donation to the developers.

I have been using Krita for 8 years, but only since the release of version 5.0 can I recommend this application. This update fixed many bugs, lags, crashes and other problems.

What I would appreciate in the future is the possibility of transferring brushes from Photoshop directly to Krita. While creating Brushes in Krita is well done, it's more convenient to import a brush instead of making one from scratch.

I recommend beginners to familiarize themselves with the application first, read the manual and learn shortcuts before deciding to start creating a masterpiece. I, for example, learn new things even after 8 years of using this beauty.

Keep in mind that I'm not a professional artist and can't judge the full potential of this app. Still, I think it's a good app and a worthy competitor to Photoshop when it comes to painting. Even so, I can create decent paintings. I have a sample image displayed on my profile.

To all drawing enthusiasts, I wish you good luck, fun and success using this application. Painting is a marathon and not a sprint, so do it with a smile! :D