If you want to work quick, dishing tool.
...and make your own nipple driver using the .69 bits at the hardware counter bucket.
If you want to ensure consistent tension on the non-drive side spokes AND have an idea number-wise where you're at for all sides of a wheel - tension meter.
...but many of us here can bypass the tension meter for the NDS consistency issue by just spinning the wheel and rapping the spokes for a rogue spoke sound test.
But as FB slightly hinted - you can go without both for awhile - and focus on simply honing skills basic to wheel building: Truing, recognizing rim response to tension and stress relieving a wheel.
Most of us here have built quite a few wheels without either...and no one has died because of it as far as I know.
=8-)