There is no app to search for. Petboost is not in the App Store or on Google Play: you add it from your phone's own browser, and the icon it leaves on your home screen is called Petboost Business. Nothing to download, nothing to update.
Open the link in your phone's own browser, not inside Instagram, Facebook or an email app. Those open their own browser, which cannot add to the home screen.
On a phone or tablet browser, Petboost offers this itself: a drawer called Get Petboost on your Home Screen opens once you are signed in. Install Web-app shows the steps for your device, or Chrome's own install sheet on Android. Closing the drawer only puts it off for a while; Dismiss & Stop Showing stops it on that device for good.
On Android (Chrome)
- Open Chrome and go to business.petboost.com. Sign in.
- Tap the three dots at the top right.
- Tap Add to home screen, or Install app on some phones.
- If Chrome asks, tap Install, not Create shortcut. A shortcut opens Petboost inside Chrome with the address bar showing.
On an iPhone or iPad (Safari)
- Open Safari and go to business.petboost.com. Sign in.
- Tap the share button, the square with an arrow pointing up. On iOS 26 or later it is inside the three dots at the bottom right: tap them, then Share.
- Scroll down, or tap View More, and tap Add to Home Screen. Leave Open as Web App on if it shows.
- Tap Add.
Check
open Petboost from the new icon. It fills the screen with no address bar. If the address bar shows, remove the icon and add it again, choosing Install on Android. Samsung Internet and Chrome on an iPhone are in the full guide.