Messaging-app operator Kik Interactive said Tuesday that it is aiming to raise $125 million through a so-called initial coin offering in September, one of the first established companies to step into the mushrooming but highly speculative market for these digital tokens.

In doing so, Kik, which has encountered growth issues, is trying to tap into the surging interest in cryptocurrencies and digital tokens associated with them. It also is experimenting with a potential way for its investors to essentially cash out of the company...