How to create .ipa file using Xcode?

In Xcode Version 10.0

1. Go to Window -> Organizer
2. Then select your app archive from archives
3. Then click the "Distribute App" button on right panel

4. Then follow the below steps

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6 : Finally select the place you want to save the .ipa file

In Xcode Version 9.2

1. Go to Window -> Organizer
2. Then select your app archive from archives
3. Then click the "Upload to App Store" button on right panel
4. Then follow the following steps

Step 1

Step 2

Step 3

Step 4Finally select the place you want to save the .ipa file

In addition to kus answer.

There are some changes in Xcode 8.0

Step 1:Change scheme destination to Generic IOS device.

Step 2:Click Product > Archive > once this is complete open up the Organiser and click the latest version.

Step 3:Click on Export... option from right side of organiser window.

Step 4:Select a method for export > Choose correct signing > Save to Destination.

Xcode 10.0

Step 3:From Right Side Panel Click on Distribute App.

Step 4:Select Method of distribution and click next.

Step 5:It Opens up distribution option window. Select All compatible device variants and click next.

Step 6: Choose signing certificate.

Step 7: It will open up Preparing archive for distribution window. it takes few min.

Step 8: It will open up Archives window. Click on export and save it.

Click Product > Archive from the menu, once this is complete open up the Organiser and click the latest version > Distribute > Save for Enterprise or Ad-Hoc Deployment > Choose correct signing > Save to destination