Although connecting two iPhones to the same Apple ID has its advantages — including expanding your or a partner's access to your documents, spreadsheets and presentations — unpleasant surprises can arise such as unintentionally revealing contact and calendar information and mistakenly sending texts from the wrong number. Whenever associating two iPhones with the same Apple user account — whether to share contacts and calendars or enable sharing your account with an assistant or partner — ensure you understand the tradeoffs as well as the benefits. The experience of associating your Apple ID with more than one smartphone is not much different than adding an iPad or Mac to your Apple account. Other than another mobile telephone number being associated with your Apple account — an anomaly that also occurs whenever associating a cellular-enabled iPad with your Apple ID — the process and settings are similar. Jump to: Data and settings transferring to another iPhone The first surprise you