Start-up investment firm K2 Global, backed by Indian and Asian billionaires, is looking to increase its stake in online mobile applications Paytm and Saavn, which are among start-ups with strong growth market strategies in India. K2 Global, which has built up stakes in Paytm and Saavn over in about two years, is raising another round of 284 million Singapore dollars, following on to the recently closed 257 million Singapore dollars .