There are only a few devices, mostly Nexus ones (at not all of the Nexus ones at that), that the bootloader lock status can be interrogated (or modified) programmatically.
So, if you are rooted and have a Galaxy Nexus (GSM, Verizon, or Sprint), Nexus 4, Nexus 5, Nexus 7 (2013), Nexus 10, or OnePlus One, then yes, there is an app (or two) that can interrogate this.
Other than the list of the above devices, I'm not aware of applicable apps.