ArkTap is a free software for Arknights.
You can use it in game by a floating window.
Show possible operators in recruitment and help you choose the best combination of tags.
Count the rolls of headhunt and show the possibility of 6★.
Recommend missions of elite materials.
Tap Version type 15 times in About to unlock this service
Tap the mission start button automatically. In that way you can put down your phone and do something more meaningful.