Ability to save in PSD (Photoshop) format for professional workflows.

"Mod" typically means the Pro features—such as 100+ brushes, 50 layers, and PSD export—have been unlocked without payment . Security Risks & Red Flags

For your security, it is strongly advised to download the official app from the Google Play Store or Amazon Appstore . If you have already downloaded the file, you can upload it to VirusTotal to scan it against dozens of antivirus engines before attempting installation. If you'd like, I can help you find:

Over 80–100 brushes and advanced tools like the smudge tool.

for the official Pro license to see if it's within your budget ArtFlow: Paint Draw Sketchbook - Apps on Google Play

Downloading modified APKs from third-party sites carries significant dangers:

Modded files are often injected with adware, spyware, or trojans. Because the original developer's digital signature is broken to modify the code, your device cannot verify its safety.