You can connect to the Municipality free WiFi in many places around the city: Villa Olmo and its park, Covered Market, gardens at Via Vittorio Emanuele II, Piazza Martinelli, Promenade Amici di Como, the harbour, and Piazza Duomo at Broletto (infopoint).
The first time you connect to the WiFi, you select FreeWiFiComo and follow instructions. You will be asked to type you phone number (your username), your email address and a 5-number password. To confirm your account just click on the link that will be sent to you via sms or email.
Once confirmed your account, you can browse for free with no time limit.
More info about the Free WiFi in Como
If you better like to rent our iPhone that comes with data just ask before you arrive for the check in.