RiyazStudio practice suite combines freeware Tanpura with licenced Tabla (with a 30-day moneyback guarantee). It's the first software that actually sounds like a real tabla player - because it uses real recorded tabla loops, rather than mechanically placing tabla bols at regular intervals. Coarse and fine pitch control sets both Tanpura and Tabla. Tabla tempo is finely adjustable and can even be set by tapping a key at the desired speed.
Practising with RiyazStudio is the ideal preparation to performing with live tabla - first because it gives the aural cues that real tabla players provide - but even more because the organic feel of the tabla loops encourages rhythmic play and helps develop your improvisational skills.