Actually android is best, Coz it has many apps and we can customize the phone like themes wallpapers etc. In some situations I.O.S (Iphone Operating System) is best, coz it runs games and apps more smoothly than android which means no lag, crash etc.
The Top 10 Reasons To Pick Android Over iPhone-
#10 Expandable storage-
We store a lot of stuff on our phones. Sometimes the built-in storage isn't enough. That's why we love how many Android phones let you pop in a Micro SD card for extra storage. Plus it's a lot cheaper than spending another $100 or so on a model with more storage
#9 Built-in navigation-
After all these years, the iPhone is still missing a built-in turn-by-turn navigation app. Google Maps is just OK if you need directions on the iPhone, but it doesn't give you the audio and visual cues that Android's app does.
We've heard rumors Apple may fix this in iOS 6, but for now, Android does maps better.
#8 More hardware choices-
If one smartphone model doesn't cut it for you, there are dozens of Android phones to choose from. Each one has a different screen size, storage option, processor speed, price, etc. If choice in hardware is very important to you, Android is your best option.
#7 No restrictions on the apps you can install
Apple is notoriously picky about what kind of apps it lets you install on your iPhone. While Google has a similar app review process for its Google Play store, Android owners are still free to install apps from any other third-party source they want.
This process is called "sideloading" apps, and opens up Android to a lot of cool tweaks and hacks.
#6 High-end Android phones tend to implement the latest and greatest hardware first
Since new Android phones are coming out all the time, you're more likely to get the latest and greatest hardware before Apple adds it to the iPhone. For example, Android phones were the first to offer 4G data speeds, killer battery life (like the Droid Razr Maxx), and cameras with amazing shutter speeds (like the HTC One X).
Apple is usually slower to adopt the newest mobile tech
#5 Customizable home screen
All Android phones give you the option to fully customize your home screen. Instead of just rows and rows of apps like you see on the iPhone, you can add widgets, control panels, and even shortcuts for speed dialing your favorite contacts.
#4 Perfect integration with all the best Google apps and services
Google makes some of the best web-based apps around: Gmail, Google Calendar, Google Docs, and Maps, to name a few. With an Android phone all you have to do is log in with your Google account once and everything syncs up.
Apple offers similar features with iCloud, but its apps and services just aren't as good as Google's.
#3 More choice for default apps for web browsing, email, calendar, etc.
There are a handful of alternative browsers, calendars, and email apps for iPhone. A lot of them are good. Unfortunately, you can't set them as your default app. For example, even if you're using the excellent email app Sparrow for iPhone, the iPhone's native email app launches whenever you click on an email address from a website or other app.
Android gives you the choice to use any email client, browser, calendar, etc. as your default app. That means you can always use the app you like the most.
#2 Android still does multitasking better
We still can't get over how bad multitasking is on iPhone. It's insanely difficult to reopen the app you want.
Android's solution is much more elegant, especially in the latest version. All you do is tap the multitasking button in the taskbar and a list of your most recent apps appears over your screen. Tap the app to open or swipe across to close it for good.
#1 Integration with social networks and other online services
We share a lot of stuff on our phones on a lot of different services. On iPhone, we usually have to open up a separate app if we want to post something to Facebook, LinkedIn, Evernote, Dropbox, and many others.
With Android, all those services become baked into the operating system as soon as you install the app. Want to share a photo you just took? You don't even need to leave the camera app. Just tap the service you want to push it to. Easy.
U can decide it by ur budget if u want buy any:-)