Apple does not allow an iPhone to be synced with multiple iTunes libraries, presumably because users would simply share songs with each other and lower already declining music sales on the iTunes Store. When you sync an iPhone with another Mac or PC, a warning pops up on iTunes that an iPhone can only be synced with one library at a time. If you proceed to sync your iPhone with the secondary computer, the contents of that iTunes library will automatically replace whatever media you had on your device in the first place. On a side note, that doesn’t include things like contacts, calendars or settings. Those are safe, but any songs or videos are not. Fortunately, there is a solution for how to use an …

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How to sync an iPhone with multiple iTunes libraries


Also published on Medium.