False clicks

Hi,

Yesterday whilst using the parkrun app, the rain was recording false clicks. Has anyone come across a device that can plug into the lightening port and basically become a hand held clicker?

still recording on the app, but not needing to touch the screen.

this would mean the phone could be kept in a water proof pouch out if the rain.

Or is there a good cover you could hold in one hand and still be able to press the screen with the other hand, like some sort of dome?

thanks