Audio mobile advertising platform Appington has announced a $1.2 million seed funding round.

The investment came from a range of angel investors including early Facebook manger Matthew Welty, Unity Ventures and an existing investment from mobile accelerator, Tandem Capital.

Appington says the cash will enable it to build out its VoiceOver platform.

This lets developers to populate games with voice prompts to improve retention and monetisation.

From the gods

A recent case study saw ARPU up 50 percent, ARPPU up 33 percent and the number of paying users up 14 percent in German developer raiX's FishFarm.

"We chose to invest in Appington because of its incredible platform and vision to heighten app engagement and increase revenue through the addition of audio," said Doug Renert, partner at Tandem Capital.

"We've already seen Appington successfully increase engagement 50 percent and one-day retention nearly 100 percent. The proof is in the metrics, and this will be a game changer in the mobile world."