Processing
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The build quality is way better than the S3, but very edgy. The HTC is still a bit better processed. But the reverse may decrease one, the slot for the SD card is made for me. Aluminum frame and leatherette, because there are nothing to complain about. And the display occupies 80% of the front side, so quite well the place has been exploited. The HTC M7 with its unibody slightly better processing, the S3 is processed slightly worse than Galaxy Note 4.
Display
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This display has an incredible 2560 to 1440 pixels, a pixel density of 515 ppi (pixels per inch). The sAMOLED consumed with black wallpapers up to 7 times less energy than lighter wallpapers. The display is crisp and sharp. With automatic brightness control over 700 candela (or whatever you call it also :-))) in bright sunlight. Farbtreu the display is all. Simply a top display, if not the best display.
Operating speed and benchmark results
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With Antutu Benchmark mobile phones reached a value of 50213 (with Lollipop 53590), ie above average. And Core with Geekbench 3 single value in 1123 and multicore value 3300 (after Lolli Update 3725 MC / 1233 SC). So top values, only trumped by the MC and S6 from the iPhone 6 at SC. Stuttering did not exist (yet). In Asphalt 8 or Modern Combat 5 with high graphics setting that was just a dream dragons !! Thus, a more than good processor. The chip is not too hot, the Snapdragon 810 from HTC One M9 has become relatively hot .. Whereby the naked Specs statements not know much about the heat and the load. :)
Battery life
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After a day of hardcore gaming which had 24% of the outlet, so a really good value. In normal use, two days. The quick charge function impressed a simple, within 45 minutes it was the battery is full. I think there's more not to write. (Long battery life follow)
Camera
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Good quality, if slightly distorted effect even in low light, the colors. The 6 Iphone camera delivers here a tad better values. But that's criticism at the highest level. Since I can not professionally assess those photos, I can not say much about it. However, these photos are very successful therefore a top camera !! The Grade 4 owned a much better camera than the S3 or M7.
Software
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Factory (Switzerland) Android 4.4.4 is installed in this country. A Lollipop update I have not got, but is yet to follow. Unnecessary Apps (bloatware) are pre-installed, for example. Local. But these apps can be, to my delight, uninstall. Very efficient is not working despite removable bloatware Android, you have to say. But one would install the Touchwiz the S6 in Android update that grade 4 would work much more efficiently.
For S-Pen I can not say anything because it is not often used by me.
Conclusion:
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The grade 4 is an ingenious phablet, with a top display and a super hardware. The camera is also great. At this phablet there really nothing to complain about. Alternatively, one can take the Grade 3 or S5.
If you have questions just write in the comments. :-)
Edit 02.05.015: 20.04.015 At the Lollipop update had arrived; brought in a whopping 3,000 points benchmark more. The perfomance is as usual top, no bugs or lag or similar Everything works fine.