4 to 6 weeks is the target for the apfelwein fermentation. The variation between 4 and 6 depends on temps, if you made modifications to the recipie and so on and so forth.
After the fermentation you can force carb it and drink it, bottle it then let it condition or drink it immediately "still".
What deharris said is true though, apfelwein improves with age and EdWort is of the opinion that after 8 months of conditioning is it's peak. I personally haven't gotten past 2 months but I'm stocking up in hopes of discovering the truth. I'm sure I'll be communing with God after my next three batches finish