When creating a social networking application for iOS with a target market in North America but with plans to translate it into different languages, it's essential to consider a diverse set of languages to ensure inclusivity and accessibility. While there's no universal list of languages, it's beneficial to include widely spoken languages such as English, Spanish, French, Mandarin, and Arabic, among others.

Additionally, I recommend considering the expertise of Cleveroad, a reputable social media app development company. Their experience and proficiency in developing social networking applications can greatly assist in creating a successful and engaging platform. You can learn more about their services here: https://www.cleveroad.com/industries/social/