State of the art technology didn't pass by Peru completely. In Lima you find numerous public places with free Wi-Fi. Some hotels and hostels as well as bigger shopping malls, a few cafes and restaurants, especially in Miraflores and San Isidro, also offer this service to their customers. All Starbucks have Wi-Fi, most are free, but at some places you are charged.
At Jorge Chavez International Airport you have free Wi-Fi at the waiting hall, at the VIP lounge, at Peru Plaza (food court) and at the national and international departure hall.
Other public places with free Wi-Fi include some parks like Parque Kennedy in Miraflores at the roundabout, the Municipality in Miraflores on Av. Larco (at the waiting hall and library), Parque de la Amistad at the corner of Av. Benavides and Caminos del Inca in Surco and parts of the district of Magdalena del Mar.