In my experience this app is really dangerous. I booked a quite important flight with the app, everything went smoothly, the interface is really nice and the results showed are consistent. However after I put my credit card info, I got the message "your flight is not confirmed because we are processing the credit card info, wait the confirmation email".
Well thats ok.
After many hours I didnt get any email, but te flight was appearing under "my flight" in the app, therefore I was really confused.
I tried to contacted them but it didnt work by phone (too late) and I dropped them an email since I didnt have choice.
Finally, I was very scared to dont have a flight, I hD to book it with another application much more reliable, but that flight was already full, therefore I had to pay almost the double for a new ticket.
After 12h of my email, they wrote me an automatic message saying that the flight was not conformed.
Thats unbelievable, I lost a very good flight for their fault, I dont see why they cannot tell you immediately if the money have been taken a and the ticket has been confirmed.
Ill never use this app again, and Ill never use Opodo either.