Keep iPhone 6 Plus Charging All Night?

Question

Hi there,
I got my iPhone 6 Plus two months ago and it's amazing. I had a 4S before for a few months before upgrading. I'd like to know, after doing much research:
1) I've read dozens of sites about how I should not keep it charging all the time. However, there are conflicting reports, so I'm going to ask here in the hopes that somebody can answer clearly. I currently use my iPhone with a JBL Dock (with speakers) as my alarm clock. Why? Because I use an app with sounds to go to sleep (it's very relaxing) and I like using the Wake app as an alarm. But is this detrimental to my iPhone? I've read so many different takes on it.
2) How can I see how many cycles my iPhone battery has been through? And how can I check out the health? I want to confirm that charging it at 99% counts as a cycle or not. The battery is amazing and lasts a long time, but I want to just keep tabs on its degradation, if at all possible.
3) I have read the Apple manual on it, but it isn't clear (at least on the web site). Any more info on the care of my phone would be greatly appreciated.
(I did read in a thread on here just a few hours ago that draining the battery all the way once a month, and then recharging it, is no longer recommended. Since I only did that the day that I got my iPhone, I feel very relived at not having done that again).
Thanks for any information.

Answer 1

Nat Harari wrote:
So it doesn't degrade the battery at all?
No, it doesn't.  If the device is at 80% or greater, then the charger drops to a 'slow charge', and then when at 99-100%, it drops to a 'trickle' charge.  That means it's not pushing too much power to the battery so it won't damage it.
Charging cycles by themselves will eventually degrade the battery.  But the design of the battery and the charger system minimizes that degradation.  While you might technically get more life out of the battery by only charging it when it is less than 100% and never charging it while it's at 99%+, the extension of life would be so minimal as to be almost pointless.  Compare that extension (maybe a few days, honestly?) to the convenience of being able to charge it whenever you want and not have to wait until it's fully discharged before charging it, and to me it's an obvious choice.
Add maybe 1% more total life of the battery compared to being able to easily avoid my device running out of power at an inconvenient time?  Easy decision.