One note about fast charging: The fuller the battery charge gets, the slower the charging rate. In other words, you might get to 50 percent in 30 minutes, then need a couple of hours to get to 100 percent. When I tested the Galaxy Note 4's fast charging last fall, I didn't notice an appreciable difference versus previous models' charging rates. But I'll take any speedup the fast-charging circuitry provides.
The two Galaxy S6 models have lower-capacity batteries than the Galaxy S5 sported: 9 percent less capacity in the S6, and 7 percent less in the S6 Edge. But Samsung says more efficient hardware and better battery management software will mean no loss in operating time. We'll see.
It's true that the hardware and software matter more than raw battery capacity to determine battery life, as iPhone users can attest: The iPhone 6 has 35 percent less battery capacity than the Samsung Galaxy S5, but the iPhone easily operates longer on a full charge.
Samsung said the Galaxy S6 uses a new touch-style fingerprint reader in the Home button, similar to Apple's Touch ID is on an iPhone. Unfortunately, I could not test the new S6 fingerprint reader to see if Samsung has improved it over the balky, difficult swipe reader used in the Galaxy S5 and Note 4 smartphones.
I hope Samsung's fingerprint reader works both smoothly and reliably; they're fundamental usability requirements, especially if Samsung expects anyone to use its forthcoming Samsung Pay system.
And I hope Samsung has fixed the bug in its Galaxy software that causes Exchange ActiveSync (EAS) to disable the fingerprint reader when security policies require device passwords. Almost any business will have that requirement, thus disabling the fingerprint reader for most business users. (By the way, those same EAS password policies do not disable the fingerprint reader on iPhones.)
Simplified software, at least for settings
The new Galaxy S6 devices don't seem to have much new in the way of software upgrades.
In my brief time with the Galaxy S6 and S6 Edge prerelease units, I could see that the Settings app was simplified, with fewer levels of options to wade through. Thus, more options appear in the main Settings app window, but it's a better approach in this case because you have to hunt in fewer places to find the setting you want.
The Camera app also seemed smarter and easier to use, with clearer presentation of options and cool tracking features to keep the focus on people and other moving objects, such as pets.
I didn't have a chance to use in any depth the other standard apps on the device, such as those from Samsung and Google, to see if they've been enhanced by Samsung or were the standard Android 5 Lollipop versions.
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