I use this app while driving; doing the exercises--and when I get home I study my strengths and weaknesses. Its a great tool to have for any singer.
BIG however, I think its due for an update with bug fixes like the mic not registering most of the time and the landscape/portrait problem.
Other than that, I would absolutely recommend this app; I just feel like the lack of updated support doesnt reflect the price of the product. Would love to give 4 or 5 stars but cant because of the bugs interfering with reflecting on my "performances" while doing the exercises. I hope this review is helpful to the developers and potential buyers.
MoneyMarine about Erol Singer's Studio, v1.9