Just be aware that merchants cancelling their participation in the Entertainment book program will have their vouchers removed from your app if you update it in-app. My wife and I both have the app on our phones. Mine is updated while hers is not. We were at a restaurant over the weekend and I could not find them listed in my app but she found it on hers. Thankfully we could still redeem the voucher using her phone. Sent an email to Entertainment book and got their below reply:-
Thank you for your email.
Unfortunately, XXXXXX Pizzeria has been cancelled as they have left the program. You should always update the app in order to have the most up to date content. Let me know if you have any other questions.
In the previous book form, voucher is still there even if the merchant cancelled during the year. As such I would advise not to update the app.
The only downside of not updating would be you wouldn't receive updates on any new merchants or restaurants.