Mikhail is right—the author’s intent is vague plus chances are that the usage of this slang word is wrong here. Or better yet, that the author meant to use “фокусы,” “штучки-дрючки,” “прелести” or “примочки” instead as in:

Штучки-дрючки / примочки = stunts:

http://www.multitran.ru/c/m.exe?l1=2&l2=1&s=������-������

http://www.multitran.ru/c/m.exe?a=3&s=������-������&sc=0&l1=2&l2=1

Навороты = frills / bells and whistles:

http://www.multitran.ru/c/m.exe?l1=1&l2=2&s=��������

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Note added at 32 mins (2014-12-12 15:28:56 GMT)
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I like Alexandra’s way of thinking, even though we can’t be sure if the author(s) meant “фирменная фишка заведения.” But if they did, “signature schtick” could do the job here!