Maven Equity Finance, part of the Northern Powerhouse Investment Fund, managed by Maven Capital Partners, one of the UK’s most active SME investors has invested £750,000, as part of a £1m investment round, in Airtime Rewards Ltd.  Manchester based Airtime is an innovative digital customer loyalty programme which enables shoppers to be rewarded, with a unique reward currency, that can be converted into a monetary credit on their mobile phone account or for additional mobile data.