Motorola's Migrate app has existed for a few years to make it less painful to switch to a Motorola device from something else. It's had support for Android, iOS, and dumb phones all this time, but the app was recently updated to remove a feature. As of September 27th, Motorola Migrate no longer supports iPhone contact/calendar transfer.

Motorola's changelog for the update only includes a notice of the removal of iPhone support. No reason is given, but it says non-smartphone and Android device transfers will continue working. The notice also includes suggestions for third-party transfer tools you can use to get data from an iPhone instead. Note, the Motorola support pages and screenshots haven't been updated yet. Here's the full text of the changelog.

Attention Migrate Users:
Sorry, but we will be removing the Migrate iPhone transfer service from the application on September 27, 2015. You may still use the Migrate Android and non-smartphone transfer services if you are on Android 5.1 Lollipop or below.
You may wish to choose another app as an alternative for your data transfers. Other consumers have used Copy My Data, Phone Copier, ShareIt, etc. which are available on most app stores.

The most likely reason for ending iPhone transfer is that it simply wasn't a good use of development resources. To make this work, you need developers to remain current with Apple's tools in addition to Android. The value proposition of Motorola Migrate isn't very strong anymore in general. Android 5.0 added the enhanced restore tool, which Motorola replaced with Migrate on some of its devices. However, the new Moto X Pure includes the proper Android restore tool.

I wouldn't be surprised to see Migrate end support for devices running Marshmallow, especially considering the new data backup features in that version of Android. The text of the changelog actually mentions Android 5.1 or below, so does that mean 6.0 isn't supported by Migrate? I guess we'll find out soon enough.