Yes, most of the tools mentioned are available for both desktop and mobile devices. You can download https://instazoom.io/ the apps straight to your phone and edit your profile picture on the go.
No, many of the tools mentioned are user-friendly and do not require advanced image editing skills. You can start with the basic features and then gradually move on to the more advanced features.
Yes, many of the tools mentioned offer free versions with limited features. You can try the free versions and upgrade to the paid versions to unlock additional features if needed.