on the text message icon.
on the text message icon. where the numbers are to let you know how many new text you have. there is a symbol of a small cell phone.what is it ?
iPad Air 2 Wi-Fi
The badge icon that appears with the Messages icon indicates that the Messages App on your iPhone is active - and, potentially, you are composing a message.
The badge icon comes about through the Continuity functions; simply tapping the icon allows you to directly pick-up the process on your iPad.
More information can be found here:
Use Continuity to connect your Mac, iPhone, iPad, iPod touch and Apple Watch – Apple Support