High quality and especially with applications running (Viber, Google Maps Navigation, etc)!

The "+" in a nutshell:
* Not that the "classic calls," OK also for Viber, Google Maps routes, and most apps! (This really is not the case for all headsets at that price, let alone low-cost)
* Good Quality. Keeping on good ear. His very correct. Perfect autonomy.

What is "average" (warning, see update at end of comment, you could have the voice prompts in French on your purchase):
* Voice prompts in English autonomy. "Plantronics Hub" Android can make adjustments on your screen if you really do not understand English.

Less than 30 euros, it seems to me a very good deal.

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In more detailed version:

Some details:
* It seems to be very well in the ear, without adding the external contour!
* The voice is in English (or German): I belong to those for whom it does not pose a problem, maybe it will hinder some, for you to see, at least given the small number of things to remember for all understand, no need to take private lessons ...
* The rated talk time and standby time is very normal very suitable! The DeepSleep fashion is huge in length, but it is to avoid that the headset is discharged when nothing is connected (forgetting to use the off button for example).
* There is a tracking app for iPhone from the packaging. I have tried with Android "Headset Battery Metter" Plantronics does not, by against "Plantronics Hub" made the case to simply monitor the battery from my Moto G 4G android 4.4.4 (there I certainly had to restart before the headset).
* It can manage two devices: not tried
* And especially it manages several types of Bluetooth profiles: not only can you make your conversations classic (classic voice telephony, without particular application) but you can also listen to music via an application (setting activated / deactivated recent Android) , use Google Maps for navigation mode (with voice guidance), etc ...
* Works with Viber / ViberOut on my Android phone.

Some features are not obvious to see in the description or photos:
* Weight: 8 grams (nothing wrong, we feel that there is something in front of the exit of the ear but we do not feel the weight)
* Autonomy 11 hours of talk (I only need half as much, but it's a pleasure to have a product that will satisfy me when the battery is worn to the point of having only half of the original capacity)
* Normal standby time with a connected device without any sound: 16 days (it is similar, it's beyond my needs and better)
* Autonomy when the unit is on, but disconnected from any device (DeepSleep): 180 days

The atria allowing only traditional telephony without application are rather numerous. Ten euros there are "no marks". At 15-25 euros you can easily find the "marks" (depending on brand) in the entry level model. Except for once, Plantronics is a good brand, but this is not the entry level of this brand! ML25 between (for example), and the M70, there is a ditch!

That's why I'm satisfied for now!

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Update (12/19/2014):

I come in the news:
* I am still very satisfied with my purchase. (I hope it will be confirmed over time.)
* For voice indication "in English," there would have been changes to the currently present description, therefore probably be on products. If given my description, you agree to have both the French than in English for some voice prompts, probably not need to read more. If you absolutely want the "in French," read the description in force at the time of purchase, I imagine that Amazon is held (if, returns when it is sold by Amazon, this is not complicated). In any event, my assessment corresponds to Article I received, in English, true to the description at the time of my purchase. And I am satisfied anyway!