There is no handheld device with electronic temperature control, like an e-nail. The only way to modulate power with wire heaters is to pulse the button, but you can't precisely target a particular temperature.
The positive-temperature coefficient ceramic heating elements provide a measure of temperature control, in that the target temperature of the heating element varies with the voltage applied. With a variable voltage power supply, you can precisely and repeatably set temperature, although you won't know what that temperature is. You'll have to dial-in your sweet spot via trial & error.
The devices using wire heaters suck; not because of wire heating elements per se, but because they use such small heating elements that reach very high temperatures. You can build your own wire heater skillet with big beefy coils, and drive them at low temps. But, there are no off the shelf skillets like this, and there are no off the shelf power supplies with
temperature control.
Imagine a BudToaster for concentrates. The guys on ECF are
less enthusiastic, but they don't get high on errl.