iOS 8.4 animations and apps keep lagging major

Try force restart:

http://support.apple.com/en-us/HT201559

Try quitting the app like this: To quit an app double click the Home button to reveal the app switcher. Flick up on the page preview of the app you want to quit. The page preview will fly away and disappear. That quits the app.

Then reset the iPhone. Press and hold both the Home button and the Sleep/Wake button continuously until the Apple logo appears. Then release the button and let the device restart. You will not lose data doing this. It's like a computer reboot.

Also make sure your phone has enough free space to operate efficiently. With iOS 8 it is recommended that you have 15-20% of the storage space on the device free. For a 16 GB device that is 2.4-3.2 GB free. For a 32 GB device that is 4.8-6.4 GB free. For a 64 GB device that is 9.6-12.8 GB free.

Close off all apps from Multitasking:

Double-tapping the Home button will bring up the running apps icons along with an app screenshot "card" above the icon. Tap-drag the app's -card- (NOT the icon) up and off the screen.

Reset the device:

Device Reset (won't affect settings/data/music/apps/etc)

1. Press and hold (& continue to hold) BOTH the Sleep/Wake button & the Home button.

2. Continue to hold BOTH (ignoring any other messages that may show) until you see the Apple logo on the screen.

3. Release BOTH buttons when you see the Apple logo and allow the device to boot normally.

I think it might be an issue with iOS 8.4. We may have to wait for an update. I and many others on the forums are experiencing lag issues with this update.

I have no lag issues with 8.4. Every time a new version comes out (going back 7 1/2 years) any problem people see is attributed to the latest version. I can point you to hundreds of posts bemoaning the fact that 8.3 was buggy, and hoping that 8.4 would fix whatever they thought was broken. There have been lag issues for 8 years. They are independent of the iOS version, the iPhone (or iPad) model, and any other variable. And they are easily fixed 99% of the time by doing some simple troubleshooting steps that have already been posted.

"You and many others" who have had a problem come here looking, and find that others have a similar problem. People who have no problems don't come here, so you rarely see a post that says "I updated to 8.4 and it works perfectly." Basing a hypothesis on the smattering of posts you see in any support forum is like surveying the people in the emergency room at a hospital, then concluding that everyone in town must be sick.

It's just worse than the public beta was so it seems something here either regressed or something new was introduced, perhaps relating to the new Apple Music service. I had no lag issues prior to this.

Either you didn't read my post or didn't understand it.

I Understand you're not having any issues, that's fine. But that doesn't mean me and some others aren't seeing new issues. It's ok, I'm sure it's a percentage and there are various factors involved. iOS is a complex beast. Cheers.

No, that was not my point. My point was that EVERY VERSION OF iOS FOR 8 YEARS has had occasional reports of lagging. Including several hundred here for iOS 8.3, which the posters hoped that 8.4 would fix. And many also said "I never had a problem with 8.2"

After you have followed the excellent instructions provided Ralph and SergZak, killed all apps to allow RAM to reorganize, and restarted the phone, if you still have a problem you have some credibility about it being an 8.4 problem. Lagging is most often caused by heavily fragmented RAM; the lag occurs because iOS has to constantly move app storage around in RAM to make space for the next app. So clearing RAM will usually fix it. It also usually isn't necessary; it will cure itself in a day or two. But there's no harm in helping it along.

Thanks! I am hoping it will get better over time. :-)

My iphone 6 is so sluggish and lag so much after updating to iOS 8.4. Like its bad. Lags on simple apps and the music app is like 5 sec lag! Home button doesnt respond right to wake up or when I try turning it off it lag and doesn't do anything. My phone is dead its lagging as i type this. It inputs the first and last letter of a word as I type it's slow respons.

It's fine for you, that you never had issues and maybe, there are people which report lagging with each new version, but this forum is for exchanging issues and possible solutions or workarounds.

I myself use iPhone and iOS since the beginning, had new devices each new schedule, updated to iOS with each new final release, and never had issues, BUT with iOS 8.3 first time and 8.4 especially I encountered terrible lags if entering the multi-tasking and switching between the apps. At this time also the home button doesn't do anything. Resetting, restarting etc. did not help as well.

I now encountered, the problem seems to be with the photo update of the recent contacts and my favorites shown in the multi-tasking screen as after reboot no faces were shown and after the lag time faces are shown for people with faces in e.g. facebook. Disabling the favorites and recent contacts result in the lag not occuring again, however, that seems to be a bug. A really terrible one as I like the quick contacts, but it makes me stupid to work with the lag.

What troubleshooting steps have you taken so far?

HI,

I reset the phone with Home and Power, I rebooted it. I recognized, rhat the issue are the pictures in the recent contacts, so I found the issue, but I'm unsure about the solution. Disabling the contacts in the app switcher is a workaround but no solution. I opened a bug report in the developer program.

Regards,

Christian