How to sync .ipa files from comp to iphone thru itunes ?

When you sync the iPhone with the computer, iTunes will only add what is new, it will not delete your apps.

Setting Up Syncing You use iTunes on your computer to set up which items are synced. Make sure you have the most recent version of iTunes (On a PC, open iTunes and choose Help > Check for Updates. On a Mac, open iTunes and choose iTunes > Check for Updates.
Step 1: Connect iPhone or iPod touch

1. Connect iPhone or iPod touch to your computer using the included cable. You can connect the cable from your computer directly to iPhone or iPod touch, or connect the cable from your computer to the Apple Universal Dock (available separately) and put iPhone or iPod touch in the dock. By default, iTunes opens automatically.
2. Select iPhone or iPod touch in iTunes under Devices on the left hand side and click the Info tab.

Step 2: Set Up Which Items Are Synced Click the respective tabs in iTunes to specify which media and information you want synced from your computer to iPhone or iPod touch.
For more information about syncing iPhone with your computer see the iPhone User's Guide:
On your computer: click here to download and view "Chapter 1: Getting Started" in iPhone User Guide.
On iPhone: Tap Safari and view http://help.apple.com/iphone/guide/.
For more information about syncing iPod touch with your computer:
On your computer, click here to download and view "Chapter 1: Getting Started" in iPod touch User Guide.
On iPod touch: Tap Safari and view http://help.apple.com/ipodtouch/guide/.

Step 3: Sync iPhone or iPod touch Click Apply in the lower-right corner of the screen. Your computer syncs with iPhone or iPod touch according to your settings.
The first time you sync iPhone or iPod touch, you are asked if you want to merge data, replace data on the service, or replace the data on your computer. After that, anytime you connect iPhone or iPod touch to your computer, iTunes opens and syncs with iPhone or iPod touch according to your settings.
You can adjust sync settings anytime iPhone or iPod touch is connected to your computer. You can only connect and sync with one iPhone or iPod touch at the same time. If you need to sync more than one iPhone or iPod touch, disconnect one before connecting the other.
Note: Syncing won't delete any contact in Yahoo! Address Book that contains a Messenger ID, even if you've deleted the contact from your address book on iPhone or your computer. To delete a contact containing a Messenger ID, log in to your Yahoo! account online and delete the contact using Yahoo! Address Book.

If I could be of further assistance, let me know. If this helps or solves the issue, please rate it.
Thanks, Joe


I’m happy to assist further over the phone at https://www.6ya.com/expert/joe_8b8c2cd6ce148309

I have downloaded a ipa file, now i'm unable to instal it in my iphone through itunes...please help

Download a program called iTools That will allow you to install it