Improper authorization in handler for custom URL scheme issue in 'Skylark' App for Android 6.2.13 and earlier and 'Skylark' App for iOS 6.2.13 and earlier allows an attacker to lead a user to access an arbitrary website via another application installed on the user's device.
https://play.google.com/store/apps/details?id=jp.co.skylark.app.gusto