Yes, the tax office has an app! Sign in with your gateway account, (do not worry as you get to change this to a PIN and fingerprint ID) and get all the info regarding your tax contributions and tax credits, if you qualify. Useful calculator can help you work out your likely tax and NI for next year too. You can also link to renew your tax credits too.  Self-employed business users will find this app a handy tool for budgeting.