Kakao-backed air quality monitor developer Bitfinder has closed a series A round, after previously raising $2.2m from investors including Kakao.

Digital textbook provider RedShelf has secured series B funding in a round backed by existing investor National Association of College Stores.

GMO reinvested in the online payment platform, also backed by Rakuten and CyberAgent in the past, as part of a series A-2 round that lifted its total funding to $5.2m.

The visual retail analytics company, backed by NTT Docomo and Sakura Internet, has boosted its latest round with $2m from Inspire PNB Partners.

The round, co-led by GE Ventures, included Robert Bosch and Yokogawa Electric and was closed as FogHorn Systems converted $2.5m of seed funding to equity.