Nexus 5 with an English interface and a Hebrew keyboard I can't figure out how to set a Hebrew keyboard while using an English interface in my Nexus 5. The only way I have found to switch to a Hebrew keyboard was changing the language of the interface to Hebrew.

Is it possible to have them both without a third party app?
Yes you can do this. For this, I am assuming you are using the stock Google keyboard. 

Open Settings and tap on Language &amp; Input. Tap on the settings icon next to Google Keyboard. Tap Input Languages at the top. Deselect "Use System Language" and then select any keyboard languages you wish to use. 

Now in the keyboard, the space bar will display the current selected language. To change to one of the other active languages, press and hold the space bar and select the language you wish to use.