For me it was about 10 hours. It’s better to make sure everything is in order and you know why they have suspended your app and updated everything to fix that issue BEFORE you appeal -describe in appeal everything you did. In your case (nudity in chat app) I think you stand no chance - nudity is what advertisets hate the most.
The problem is that there was no explicit showing bare breasts, buttocks, genitals, intercourse… etc.
Just received the email this morning and then removed all images. Then with no images showing in the app I appealed.
Then manually reviewed all images for the last 3 days and enabled only the clean ones. And for clean I mean no guys without shirt flexing muscles, no girls in bikini, innocent cleavages… etc… Inquisition time 100%
I’m using Admob for 2 years and had no problem until now, I had a Google Play scare on april 2014 when the no nudity ban, but nothing from Admob until now.
Crossing fingers and looking for alternative networks, I think I will go with Mopub.
Well, happy ending for now. The ad serving has been re-enabled!
The good thing about scares like this is that I have been forced to move my ass and now I have a mediation Mopub mediation stack working with several alternative networks ready.
And I have a JSON file on the server that I can modify to change between the Admob & Mopub mediation stacks without releasing a modified APK.
In my case I explained to them what I did to fix the problem with the images.
Quoting from memory, something like this:
"To fix the reported infraction we have removed all user images except the ones from the last 3 days. These we have reviewed manually one by one to make sure they do not contain: strategically covered nudity, sheer or see-through clothing, lewd or provocative poses, close-ups of breasts, buttocks, or crotches.
From now the manual revision of images before they are published will make sure that no wrong images are published in the app."
I guess that you have the fix the problem, explain well what are the steps you have done to prevent that in the future and most important, cross you fingers…