TracingPad

This is a good lightbox app, but it is not a tracing app. It's meant to be used with actual paper not to impose digital tracing paper for your stylus. If your looking for a digital tracing app this isn't it. If you want a great lightbox app look no further.

Controls are hard to fine tune. Buttons nearly unreadable, needs higher contrast between text and button. WARNING! This app accesses images that are otherwise hidden, as in placed in a secure folder. It accesses ALL images saved on phone regardless of permissions.

This is a light box app that displays an image and locks the screen to allow you to draw over it (using paper). It requires NO extra permissions, which automatically makes it ★★★★★ more sensible than every other lightbox app.