Both Easydcp Player and Davinci Resolve Studio can play DCPs and lets you lower the quality settings so you can play them on slower computers. In Resolve you can use the built-in Kakadu decoder or the Easydcp Plugin to play dcps.
Easydcp player and the Easydcp plugin in Resolve support playing encrypted DCP with a DKDM.
Only Easydcp player can show the subtitles in DCP with interop/SMPT XML MXF subtitles.
These can be used to check the DCP for some common problems or to screen the DCP on non-DCI projectors. You could use the trial version of Easydcp Player (It plays only the first 15 seconds of a DCP) to check if the DCP loads correctly, the colors are OK, and even do a file hash check.
Both Davinci Resolve and Easydcp Player supports Interop/SMPTE DCPs. And can export DCPs to Prores Quicktime files with P3, rec709, or custom color/gamma encoding.
Both can play DCPs with offsets on audio and video and reels.
In Davinci Resolve you can enable P3 in the viewer and view DCPs in P3 colorspace on newer Macs. See this post for more info.
-They need fast computers, Both can play 2K DCPs on a modern quad-core CPU PC.
-Your DCP will look and sound different in a movie theatre than on your typical PC. DCPs can be 12 bit 2.6 gamma. while computer screens are usually 2.2 gamma 8 bit.