Add it to your Home Screen. No app store.
How to install
iPhone
Open grasp.fm in Safari
Tap Share
The square with an arrow at the bottom of the screen.
Choose Add to Home Screen
If you don't see it, scroll down the list.
Tap Add
The icon appears with your other apps.
On iPhone, calls come in only when you open the app from the Home Screen.
Android
Open grasp.fm in Chrome
Open the menu
The three dots at the top right.
Choose Install app
On some phones it is called Add to Home screen.
Confirm
The icon appears with your other apps.
Computer
On a computer everything works in the browser. For your phone, open grasp.fm there.
Invitation-only for now