Shoreditch-based start-up firm LoopUp Group plc (LON:LOOP) got off to a flying start as it debuted on AIM on Wednesday, with shares adding 10%.
The company came to market raising £8.5mln in an initial offering at 100p, giving a market cap of £40.8mln.
Shares in early deals in London quickly rose to 110p.
The firm has developed software to make conference calling in business easier, reducing muffled noises and allowing users to share content while speaking.
Steve Flavell, the co-chief executive officer of LoopUp, said the float was a "milestone moment" on the group's journey.
"The reception from investors has been positive and encouraging, and reinforces our belief that our differentiated product, business model and plans for the future provide the foundation needed to deliver on our potential as a public company.
"Our focus will continue to be on delivering an exceptional product and service to our customers around the world, supported by the funds we've raised and emboldened by the faith our new shareholders have placed in us. These are exciting times."
The firm plans to use the cash to increase investment in its new business acquisition structure, create an online sales channel and further enhance the product.
The funds will also enable the group to restructure its balance sheet by paying down existing debt.
During the first six months of 2016, the group has signed up over 200 new customers, including two major account wins which, based on their historic usage profiles, have the potential to become the group’s largest customers.
Although based in Shoreditch, home of the so-called Silicon Roundabout, the group also has offices in San Francisco, New York, Boston and Hong Kong, and four data centres in London, Chicago, Hong Kong and Sydney.