At around noon on a recent weekday, the Roppongi branch of Shamrock by Abbot Choice, a Tokyo-based Irish-style pub chain, had a bustling lunchtime crowd.

Koichiro Tawa reached for a menu and ordered a hamburger special — with melting cheese, a green salad and mashed potatoes, along with a separate plate of rice. It's a dish that is familiar to him, as he visits the restaurant almost daily. But his relationship with the pub goes a little deeper than that of a regular customer.

Last October, Timers, a Roppongi-based startup firm selling smartphone apps where Tawa is chief operating officer, asked — through the company website and fliers it distributed to the area's establishments — whether any local restaurants would offer the firm's five employees free lunches as "barter" for creating a website for their eateries.