Android/Adware. Startapp is Malwarebytes’ detection name displayed for the Startapp Ad SDK bundled in various apps, which at times can be very intrusive.
Aggressive advertising will be displayed and difficult for the end user to identify which app is displaying. Advertising functionality is hidden and user is not made aware of the ads during installation.
Apps with this Adware can be found in the Play Store as well as third party app stores various forum posts.
Malwarebytes for Android protects against Android/Adware.Startapp.
These apps can be uninstalled using the mobile devices uninstall functionality, but these apps can be made available under another name. That is where Malwarebytes for Android can help you, by identifying these apps and removing them.