an app called "Allow"

the name of this app makes it almost impossible to search for info about it !
does anyone know what it does and where it comes from ?
I tried unsuccessfully to install an APK but noticed the error message mentioned Allow, and that this appeared with a (shield-looking) icon, so I looked for it on my phone and disabled it (along with the usual dire warnings) - and lo & behold, I was able to install the APK
is this app important or is it just designed to stop me installing things ?

no - not a permission; I didn't just switch it off
I disabled it - after finding ot in a list of apps..

I am sufficiently paranoid that I have NEVER visited the playstore. The only apps are those pre-installed on my phone. That is why I was trying to install an APK (and succeeded).
This "Allow" was an app, pre-installed, intended to defeat my loading something that google did not "know" about. It is cunningly named in order that it is difficult to investigate, and meant to make you think that it is a "permission" - you fell for that one ...
Please believe me - it is an app - and stop trying to tell me it is just something that I ticked !