You should connect to one of these networks, depending on the country:
USA: T-Mobile
Turkey: Turk Telecom
Australia: Telstra
Canada: Rogers Wireless or Telus
UAE: du Mobile
Brazil: Claro BRA
Brazil: AT&T
Egypt: Plus
Japan: Docomo
Malaysia: Umobile
Morocco: Inwi
New Zealand: One NZ
South Africa: Vodacom
Switzerland: Salt
Thailand: AIS
Singapore: Singtel
Tunisia: Orange TN
Vietnam: Vietnamobile
Norway: Telenor
Your phone should connect automatically. If it doesn’t work, click here for the DIY section.