In the US Xero have launched, TaxTouch, a tax app designed to help contractors & freelancers stay on top of their accounts and to help them remove the tax burden.
Unfortunately if you search the UK apple store the app is not currently available in the UK. Being specialist Contractor Accountants we will keep our eye open for its UK launch.
TaxTouch appears to be a lighter version of the full Xero app and hence is available at a lower monthly cost.