Your friend is right. Everything on your iPhone will be wiped out. That's because you're going to transfer photos from the Mac that is not synchronized with your iPhone, which would make you either fail to move photos from Mac to iPhone or erase any data on your iPhone. iTunes can not help you achieve your purpose. Here I'd like to show you an available way to transfer photos from Mac to iPhone.
iOS Transfer (Mac) is specially designed for Mac users who have Apple portable devices. It enables you to transfer your photos from Mac to iPhone without any files losing, so that you can enjoy pictures downloaded from any Mac with iPhones!
Note: It's fully compatible with MacBook Pro, MacBook Air, and iMac with Mac OS X 10.10, 10.9, 10.8, 10.7, and 10.6. And it supports different iPhone models available based on iOS 8 including iPhone 6/6 plus, 5s/5c/5, iPhone 4s and iPhone 4, etc.
Free download the trial version of iOS Transfer (Mac) and install it on Mac.
How to Transfer Photos from Mac to iPhone without iTunes ?
• Step 1: Connect your iPhone with Mac
Connect your iPhone with Mac. Launch the program. After your iPhone is detected by the program, you will get the starting window revealing your iPhone.
• Step 2: Transfer photos from Mac to iPhone
Click "Photos" on the left, you will get the Photos window. At the top of the picture, there's an icon "Add". Click it to browse your Mac for pictures you want, then select them, and click "Open" to transfer them to your iPhone.
In just a second, you can see those photos are moved from Mac to your iPhone. You can crate a now photo albums to put them in by clicking "Add Albums" on the bottom-right.
Now you would find that iOS Transfer (Mac) is really a reliable friend of iPhone and Mac. It's very easy to transfer photos from Mac to iPhone without iTunes and any data erasure which bothered you before. And it's a two-way transfer application that you can perform data transfer between iPhone and Mac freely.
Try iOS Transfer (Mac) to transfer photo from Mac to iPhone freely.
Note: If you are a Windows PC user, you can try iOS Transfer to transfer photos from PC to iPhone.
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