A new smartphone app from Best Buy is offering to give moviegoers special insights into the upcoming animated film “Despicable Me”. But even days before the picture’s debut the app is getting some seriously divided comments—kind of a mobile version of Siskel & Ebert’s patented “thumbs up, thumbs down”.

The app, available at www.BestBuyMovieMode.com and in various mobile app stores, claims that users who download it to their smartphone, then turn that phone on in the theater at the start of the picture, will get a surprise at the end credits. The app is seemingly able to translate the high-pitched gibberish spoken by the Minions, little yellow clone sidekicks of the movie’s super-villain hero.

Following that so far?

Those little yellow doughballs are the most identifiable and potentially kid-friendly element in the movie, so of course they’re all over the movie’s advertising and branded tie-ins from IHOP, American Express and Kodak, among others. IHOP’s got the Tater Tot-shaped guys bouncing all over the menu this summer, including new lemonade drinks and, yes, Tater Tots.

Their barely intelligible machine-generated speech is also an ad asset. Most of the big characters in animation these days are voiced by big stars, which makes it difficult to call them in for more than a few seconds of voiceover work for TV commercials. That’s why you heard lots of John Ratzenburger in those “Toy Story 3” spots for the Postal Service and very little of the Woody character, voiced in the movie by by Tom Hanks, and here by…somone else.

But the Minions can be deployed at will with their true electronic voices intact, so they’ve been popping up all over the brand spectrum. And most intensively on NBC, Universal’s TV partner, in interstitial ads for the channel’s show line-up.

The Best Buy “Minionator” app is undoubtedly a few levels of sophistication above simply movie-shaped food. In fact, according to a report in Variety , it’s intended to associate the electronics chain with entertainment content in an entirely new way. Where once consumers didn’t think of Best Buy until the movies were off screens and on DVD and Blu-ray, this new app is meant to forge links with live, active “entertainment experiences” while they’re still in the theater.

Once again, that’s in the theater. As in, “turn your cell phone on while you’re in the theater.” With other people around you. And right after having viewed the standard movie-theater boilerplate about being courteous and silencing your phone while the movie’s playing.

That’s one major factor contributing to the severely split decision on this Best Buy app, at least before users have a chance to use it in the theaters. Best Buy seems to more than a few movie fans to be inserting the thin end of a wedge that could lead to some anti-social behavior in the dark.

To be fair, both Best Buy and Crispin Porter + Bogusky, the agency that worked to create the Minionator app, point out that before the app can be fully activated the user must silence his or her phone’s ringer. Once that’s done, reportedly, the app will also dim the phone’s screen to minimize the annoyance to those nearby. And while it’s hard to tell before the July 9 launch date—the app includes a countdown clock—it doesn’t seem to let you fire up the app without first silencing the phone.

But the phone will be on while the movie’s playing, and chances are it will be in users’ hands, as opposed to in their shirt pockets and set to vibrate. While the Minionator app will only work during the end credits, users must set their phones up before the movie starts. This is a movie aimed at least partly at kids; they have a hard time leaving Mommy’s iPhone alone at the best of times.

There will also be plenty of users who forget to set the phone up before the movie and will only do so at the end. So the last few minutes of “Despicable Me” may see an outbreak of frantic smartphone turn-ons.

And while reports have suggested that the app will “discourage” texting on those smartphones during the movie, apparently that dissuasion will come from the dimmed screens. But guaranteed some bozo will insist on trying to text during the picture, no matter how low the visibility. (And I’ll lay you Vegas odds he’ll be sitting next to me while he does so.)

And will the app work if users silence the call ringer but keep the alert beeps for incoming texts, Facebook updates, new e-mail, etc.?

I’ve spoken to marketers who are using both mobile and in-theater ad channels in their campaigns and asked why they rarely integrate the two with on-screen ads that offer mobile short codes users can text to get content or some other premium. Almost invariably, they’ve cited the strong resistance of theater operators to the idea of getting the audience to use their cellphones once the show—or even the ads—start.

Best Buy is breaking an informal but real social barrier here, and the gamble has to pay off both for them and for the whole audience—including the portion not using the app. If the result is too disruptive, they could risk serious flack from moviegoers, theater operators and perhaps even the studios they want to hook up with.

At least some portion of that audience is primed to object to the use of smartphones during a show. “Despicable App for ‘Despicable Me’” reads the headline of the “Independent Eye” blog on the IFC.com site. Meanwhile on the iTunes App Store one consumer wrote, “Horrible idea…Someone should be publicly flogged for this app.”

And a post on Cinematical.com (headed “Wait, Cell Phone Use Encouraged during ‘Despicable Me’?”) drew this comment from one reader: “Thanks for the heads up and the notice to avoid seeing it in the theaters. Oh well, there goes my $10 to the studio.” That’s not what Universal Studios wants to hear.

My own view? Apart from possibly undermining the movie experience, Best Buy also runs a risk of overpromising and then not delivering on audience expectations. The TV spots promoting this app gloss pretty quickly over the notion that the app only works in the end credits.

It also has to work, something we all won’t know until the movie debuts. Some attendees at the late-June premiere reported that the app failed to function properly during the credits.

And while Best Buy has gone to some lengths to make sure the app is available to all kinds of smartphones, they may not have gone quite far enough. In the iTyunes App Store, the app currently has 90 five-star ratings—and 95 lowest one-stars. That’s not because the app doesn’t work, but because users of iPod Touch come in expecting that it will be available for their devices, and it’s not.

Since it’s hard to tell at this point exactly how the app works, it’s difficult to know whether Best Buy should have thought of this cross-platform problem. If the app is unrelated to the phone function—for example, if it synchs up to the movie via a timer, and that’s why users have to turn it on just before the movie starts– they should have sprung for the iPod Touch version. After all, youngsters are still more likely to own one of those than a smartphone. And Touch owners have been trained to expect that most of the games available for iPhones are also available to them.

I should add that if the app doesn’t degrade the movie experience, it sounds very cool. And Best Buy says that when “Despicable Me” eventually makes it to DVD and Blu-ray, viewers at home who use the app will be able to get translations for everything the Minion characters say throughout the movie—not just at the end credits. Honestly? I’ll be parked on my sofa with my Minionator on.

And I’m truly interested to see what other movie properties will fit into Best Buy Movie Mode. How many other films are going to offer characters speaking gibberish in need of translation?

Of course, “Transformers 3” is coming someday, I suppose.

Update: Since posting this, I’ve heard from Best Buy with a few details that help clarify how this app will work and reassure me a bit that the experience won’t disturb other audience members. For one thing, it has been explained to me that an on-screen cue before the movie starts will remind users who’ve downloaded the Movie mode app to activate it before the picture starts. With that done, users can then put the phone in their pockets; when the end credits approach, the app will send a vibrating alert to notify them that it’s time to take out the phone and watch for the translations of the Minions’ dialogue.

Best Buy clarified another question I had, too. The reason there’s no iPod Touch version of this is that the app uses an audio cue to send the alert and start working once those credits begin to roll. Audio needs a receiver to hear that cue– something the Touch device lacks, hence no Touch-compatible app. That’s not to say ruling out a popular device isn’t a problem in marketing around a movie that quite clearly will attract an audience for whom smartphones may be out of reach but who are eminently well supplied with Touches. But at least it’s an explanation.

So now I’m ready to buy my ticket, switch off my ringer and wait for the call to see the Movie Mode app in action. Pass the Sno-Caps, please.