If you were planning to fill up an SD card with apps on a Windows 10 tablet at launch, it looks like you might be waiting a while. Microsoft has opted to postpone the ability to save apps to SD cards until "a later release."
The missing feature was first spotted by Microsoft guru Paul Thurrott, and a quick check on the Windows 10 support forum revealed the following message from a Microsoft representative:
"We have actually made the decision to postpone the apps on SD functionality to a later release. While I know this feature excited many of us, we didn't feel like it was ready for prime time. Our goal is to delight users with everything that we build, and we truly feel that that is what will happen once we have fully built our vision for this feature."
This is pretty unfortunate news for those that may be dealing with limited device space on a Windows 10 tablet, but the good news is that the feature is still planned to make an appearance in a future update.
Update: Correction to remove mention of phones. As pointed out in the comments, this only applies to Windows 10.