An Army article notes an innovative attempt at supporting the religious free exercise of US servicemembers in the field:

The easily deployable tent structure, also known as a “sacred shelter” by developers at the U.S. Army Natick Soldier Systems Center, provides units with a small worship facility that can be set up rapidly in the field.
 
“This provides a facility for spiritual fitness, whether or not a chaplain is available, in an austere environment,” said Chaplain (Capt.) Andrew Shriver, 421st Multifunctional Medical Battalion chaplain.

The “portable chapels” were based on Chaplain Shriver’s own design from 2007 in Afghanistan for Soldiers who were constructing new FOBs.  They are designed to be cheap, easy to assemble, and even have partitions so separate faiths can be exercised simultaneously.

Interestingly, when the unit at Wiesbaden, Germany, tested out the prototype, the tent had a demo set up.  While a “stereotypical” religious demo might have included something like a cross, Chaplain Shriver showed a setup for an Islamic prayer room: