The freemium model pertinence depends indeed on the free user cost. A service for which the cost in minimal (i.e. no support, low bandwidth or storage needs,...

The freemium model pertinence depends indeed on the free user cost. A service for which the cost in minimal (i.e. no support, low bandwidth or storage needs,...) for free users, could benefit from it as a marketing tool. The perceived added value for paying users should be significant, obvious and justify the fee.