Can You Use Xactimate on a Mac?

As of March 2013, the answer is no.  You cannot run the software on your Mac computer.  However, with the release of version 28, which Xactware calls 'multi platform', it looks like they may be inching closer to full Mac functionality one day in the future.

The goods news is that you can use one of several Xactimate apps on your iPad, iPhone or iPod touch.  The apps are free to download at the Apple app store. You will need your Xactware ID and password to link everything together. Oh, and you don't need two licenses to use your software and the mobile application.  Thankfully, you only need one.

"With Xactimate mobile you can receive an assignment, build a model of the structure using Sketch, estimate for structural and contents, settle onsite, and then upload the assignment back to XactAnalysis – all from a mobile iOS or Android device.
And thanks to cloud-based technology, the mobile version of Xactimate works seamlessly with Xactimate’s desktop and online versions..." (source:  Xactware.com) 

Here are the mobile devices (including android and pc tablets) that Xactware says work best with the current apps:

Apple

• Apple devices which support iOS 6

*note:  you will need a data plan AND an Xactimate online account.

Android

• A device using Android 4.0.3 (Ice Cream Sandwich) or later

 *note:  you will need a data plan AND an Xactimate online account.

For the best application performance, Xactware recommends the following Android devices:

Tablets

1. ASUS Transformer Pad Infinity, Model #TF700T

2. ASUS Nexus 7, Model #ME370T

3. Samsung Galaxy Tab 2 (10.1), Model #GT-P5113

4. ASUS Transformer Pad, Model #TF300T

Phones

1. Motorola Droid Razr, Model #XT912

2. HTC One X, Model #S720E

3. Samsung Galaxy S II Epic 4G Touch, Model #SPH-D710

4. HTC Droid Incredible 4G, Model #ADR6410

5. Samsung Galaxy S III, Model #SCH-I535, SCH-R530, SGH-I747, SPH-L710, SGH-T999

 Source:  Xactware.com