Some of the UIs are badly imitating UIKit, like Zoosk. They still often replicate the navigation concepts, UIKit shadows (skeuomorphism), widget sizes … - I don't think the stock look & feel is dead yet.
By "amateur" I mean that I think the typical app consumer is getting pretty good at spotting stock UI and tends to equate that with a slapdash app, justified or not.
I took the time to analyze Top Grossing US without games. I've gotten a lot of inquiries about HTML5 based apps recently, so this was interesting.
#3 MLB, stock; #5 Pandora, stock; #12 MotionX GPS, custom; #17 and #26 comics, slightly customized navigation bar & stock tab bar; #27 Zoosk, faux stock UI; #30 eHarmony, stock; #38 TeleNav, stock; #46 WhatsApp, stock; #52 iTranslate, custom; #68 Nike+ GPS, stock; #72 Camera+, rather custom; #74 MyCalendar, stock; #81 Pages, stock; #83 DC Comics, slightly customized navigation & stock tab bar; #85 Grindr, sotck; #86 Instaframe, custom; #88 Badoo, stockish; #90 Free Music Download, stock; #93, Palm Reader, custom; #96 TurboScan, stock; #97 iMovie, stock where applicable.
Some of the UIs are badly imitating UIKit, like Zoosk. They still often replicate the navigation concepts, UIKit shadows (skeuomorphism), widget sizes … - I don't think the stock look & feel is dead yet.