iPhone 4S w/ iOS 6, any risks in finally upgrading to 8.4? I have iPhone 4S running iOS 6.
I've never upgraded to iOS 7 since at first I didn't like the new graphics.
but overtime, apps are not being supported anymore. some simply don't work, and some can't be updated as they require at least iOS7. for example, on whatsapp, I can no longer preview about 25% of the messages I'm receiving. It's very sporadic, sometimes It lets me and sometime it doesn't.

So is it about time to finally upgrade? Any risks involve? I guess I can only update it straight to the latest 8.4, right?


Any way to upgrade to iOS 7? is it recommended?
I've read the screen is too small on iOS 8 so you can barely see the email you compose. is it the same with 8.4 as well?
will it be really slow? my 4s with iOS 6 is already kinda slow.
I only have 2.5GB free, can I install it straight from iTunes and it will be ok too?
are there serious Wifi problem with 8.4?


Anything else I should consider?
To answer your questions in order:
1. No, you can only update to 8.4.
2. I don't have any problem composing emails with 8.4. I believe that there is an Accessibility setting for font size, anyways.
3. YMMV. My iPhone 4S ran great on iOS 8, but some don't have that great of luck.
4. I think 2.5GB is enough to download.
5. I believe any connectivity issues with iOS 8 were fixed within the first few updates.

iOS 8.4 ran well on my iPhone 4S, but when I gave it to my Mom, when I upgraded to an iPhone 5S, I've noticed that for whatever reason it doesn't work as smoothly as when I had it. Also iOS 9 is right around the corner in the fall, likely next month, stability and performance are what iOS 9 is mainly addressing and the iPhone 4S will get that update, so you might just wait for that.

I haven't really ever had any major problems with iOS 8, I think it is pretty safe to download.