Do not buy! Scam.
Response from developer
We are sorry to hear you had a terrible experience. However, the app is not asking to pay for every single part, it is only 1 payment for all the IAPs provided to unlock the whole content of the app. We are working on the crash as it seems you had a bad experience, this should not happen again. On the other hand, if you are not happy with the product we can always process a refund. Please email us to contact@etips.com and we can work it from there. Thank you and sorry for the inconvenience that this might have caused you.