Smartstep is the tariff where the price of calls varies on your usage of the phone. Basically, calls to the same network or landlines cost 30p/min for the first three minutes of usage each day, then 5p/min thereafter. Crossnetwork calls are all 40p/min, and texts are 12p for the first three you send each day, then 9p each thereafter.
Smartplus is the old-style plan, with peak calls to the same network and landlines 30p/min, and off-peak calls 5p/min. Crossnetwork calls are all 35p/min anytime, and texts are all 12p.
So if you use your phone a lot at peak times, switch to smartstep!
