You can easily save to Mindstone from your Android device by using the Share button. You can find the Share button in your device's menu or within a share menu in an app.
Saving via the Share Extension
Tap on the Share button. You'll find a list of share options.
If Add to Mindstone does not immediately appear, tap on 'More' to view your full list of apps.
Simply tap on the //m icon and move it up to your favourites so that it is always accessible.
You can always email your link or add it via the web application if you can't find the Share option. Learn more about sharing via email by reading How to Forward an Email or Link to Mindstone.