Dear *insert website name,*
Please stop asking me to your mobile app. I don’t want want to use it. I don’t care if you think your app is the bees-knees. If I wanted to use your app, I’d go to the app store and download said app. But I didn’t do that. Instead, I’m writing this letter to make my stance clear:
I prefer to access your service within the comfort of a browser, thank-you-very-much.