There are IOS apps but there are no LEGO apps .Try gameloft for the IOS apps .
Yes there are many fitness app in market for both Android and iOs. There are a lot of third-party iOS apps that are compatible with Apple watch as well as iPhones which can count footsteps, kilometers, calories burnt, etc. But there is no other app as the original Apple health. This app can make the best use of sensors present in iPhone as well as Apple watch.
You can only play iOS apps on an Apple device or a device which has the App Store.
iOS 4.2.1 is quite outdated, and many modern apps are no longer compatible with it. However, you can still download older versions of apps that were available around the time of that iOS release, such as basic utilities, games like "Angry Birds," or social media apps like Facebook. Additionally, some classic apps like Safari, Mail, and iTunes are built-in. For the best experience, consider using the App Store on a device with a more recent iOS version.
It does not delete your apps I updated mine and still have my apps
The new apps you get on iOS 4.2.1 and higher are voice memos but it will require headphones with a speaker and game center.
You can get free apps without a computer for iOS 6 or 7, however you can not get paid apps for free.
The best calendar software for iOS devices is the Reminder app that comes with the iOS 5 update. My Calendar for Facebook is an app that is useful for the computer. Both of these apps help with reminders.
There are a number of music making apps on iOS including Music Studio, GarageBand, KORG iKaossilator, and SunVox.
There are a number of Klondike Solitaire apps available for the iOS devices. To find Klondike Solitaire apps or other games for iOS, visit the iTunes app store.
No, iOS apps are developed in a different language to Android apps and aren't directly compatible. In multiplayer mode however, you can play with other users regardless if they have an Android or iOS device.
only if you have a jailbrake