Paying on the web or in the app
You can subscribe in the App Store, in Google Play, or on the web. It's the same plan either way.
Why the web costs less
The app stores take a cut of every subscription. Paying on the web skips it, so you keep the difference. Codes from a friend or a partner only work on the web.
On iPhone in the US, the plan picker offers Pay on the web. Anywhere else, sign in at app.nstinx.com in a browser to subscribe there.
Changing or canceling
Open Settings › Plan & billing. Web plans are managed from there. App Store and Google Play subscriptions are changed or canceled in your store's settings; the app opens them for you.
Restore purchases is on the plans screen if a store purchase doesn't show up.
Still stuck? Write to support@nstinx.com, or use Send feedback in the app's Settings.