I was told that all androids are like that and to go with the iPhone.
An equal Android and iPhone will probably find a bit more battery usage on the Android. A bit. But performance depends on the phone. My Note 3 is no more noticeably laggy than my Windows 7 (I refuse to run Windows Hate) laptop. Granted it's got a 2+GHz quad CPU and 3GB of RAM to run little Java apps, which means that, for a few more years, at least, it'll be as fast as my brain can follow. My Samsung Precedent? Sorry, but unless you're still in your teens you're not going to live long enough to wait for that phone to wake up. (I have one sitting right on my desk.) Same manufacturer, same operating system, TOTALLY different operation. (The Note 3 is a bigger and faster phone, of course, yet I get better battery life from it than I do from the Precedent.)
iPhone? Too "for the rest of them" for me. Half the apps I run (I run mostly utilities) aren't even written for the iPhone, and some of them probably wouldn't run on it if they were. (Is there even a Wireshark equivalent for the iPhone?) I prefer a computer I can work with, as well as on. (The first version of Linux I installed was on floppies, and had to be downloaded from bulletin boards.) iPhone is a tool you use, pretty much the way it was made, and not much else. Android is a tool bed on which you can run many tools. Why carry around a belt full of tools when one tool, with lots of icons, can do the job? (Try doing a good network analysis with an iPhone - with free, or almost free - apps.)
It's not iPhone vs. Android that will make the difference (except in your wallet - you pay a lot of money for that apple with the chunk bitten out of it). Try a top of the line iPhone, then try a top of the line Android LG G2 (if you don't care about ripping out a shorted, melting battery, or using an external SD card, which I do), or a Note 3. I don't think you'll find the iPhone snappier or faster. If you REALLY like the iPhone look, there are launchers and pretty faces for Android phones (for free) that make them look like iPhones. Yet you'll probably get a better phone for less money with Android.