I didn't realize that, off the top of my head. Waze will show it just fine, in the upper right.
Yup. Waze /always/ shows the speed limit if it has the data, even if you do not have a destination set. This is so handy, and I don't know why other apps don't do this. Google owns Waze, so I'm not sure why this isn't a feature in their own Map app.
This, along with other very minor features, is why I keep using Waze as my local driving app, and Google Maps when I need directions outside my normal driving area.
It's very handy in this part of Texas to have something telling you what the local speed limit is even when you aren't actively getting directions. Sometimes I take a side street to avoid something, and due to the way our DPS handles things, there's no speed limit sign for quite a while. Along Ranch Roads (RM) and Farm to Market Roads (FM), it can be a mile or more before you see a speed limit sign.
Ignorance of the speed limit doesn't keep you from getting a ticket though.