I Have Jailbroken My Iphone 4 On Ios

Should I upgrade my jailbroken iPhone from iOS 7 to iOS 9.3.x?

If you're jailbroken of iOS 7, consider yourself extremely lucky. I have an iPad 4, which is jailbroken on iOS 7, and it is almost the smoothest jailbroken device that I have ever run in my life. There are some features missing that you might possibly crave, such as the visual effects from iOS 9 (Multitasking, the Music app, and some others), but otherwise staying on iOS 7 is a good deal.But if you really want to upgrade for another reason, then I'd recommend waiting until 30th July when the Black Hat USA 2016 occurs, since it is rumored that Pangu will release the iOS 9.3.2 jailbreak then. If that occurs, then you could upgrade and jailbreak.If not, then it's up to choice. One may give away the freedom of superuser access for new features and an updated firmware. There are pros and cons to both.UPDATE 1: iOS 9.3.3 has been jailbroken. It is a semi-untethered jailbreak released by Pangu and is only available for 64-bit devices, but it is smooth and stable as per most reports.Only update to iOS 9.3.3 if you have a 64 bit device.

Can my Apple iPhone 4 be updated to iOS 9.1 if jail broken?

Not possible. Apple does not support the iPhone 4 to update to IOS 9. You can install the IOS 9 theme( of available)  from the winterboard tweak on cydia. That's the most you can do.

Is it possible to upgrade my jailbroken iPhone 4 from iOS V 5.1.1 to iOS V 6.1.2 so I can still have the latest jailbroken version?

Nope. Stay where you're at for the time being. There is currently no jailbreak for iOS 6.1.4. The highest jailbreakable version as of now is 6.1.2, and I would not upgrade unless you have your SHSH Blobs saved somewhere, just in case you need to downgrade.

How can I jailbreak my iPhone 4?

In order to answer that question, first you need to figure out your iOS by going to settings, general, about, version. If the version starts with a 7.X.X or greater, you're good to go. If not, it's best to update first by going to settings, general, software update. After updating to iOS 7, go to this website, http://en.7.pangu.io and click on mac or windows depending on what computer you have. Then download and install the application. Open it, plug your phone into the computer, and do exactly what the application says. After all is done, you should have Cydia installed on your phone.

Is Bitcoin in Breadwallet on a jailbroken iPhone 4 running iOS 7.1.2 secure?

This is like asking if it's possible that your car can get stolen in a bad neighborhood if you leave the keys in it and the doors open and your wallet on the dashboard.Of course it can get fucking hacked. Don't jailbreak your damn old phone. It's insecure enough as it is since you've missed out on years of security updates.

What is the effect if I jailbreak an iPhone 4?

I didn't quite understand what effect are you referring to? Positive or Negative?Anyway, I will list down both for you to decide and is applicable on any iPhone or iPad models.Positive Effect:Customization - One of the downsides of iOS is its lack of customization which is eliminated when you Jailbreak.Circumventing Restrictions - iOS can be fairly restrictive, which is again eliminated by Jailbreak.Functionality Upgrades - Apple's often slow to add features to iOS, Jailbreak shows you how its done !Troubleshooting Problems - You may at some point install an app that's not compatible with your device, and your device will restart into safe mode. Not to worry, however, as you can always troubleshoot problems with Jailbreak apps.Negative Effect:Goodbye Stability and Safety - While jailbreaking can provide you with plenty of options to increase the functionality of your iDevice, it can also cause things to work unexpectedly. Little extensions and add-ons can cause applications to crash.Updating iOS is not Fast or Easy - Updating a jailbroken device sucks. When you update, you lose your jailbreak, need to re-jailbreak, and then re-install all your jailbroken apps and extensions.Restoring Often - Jailbreaking is fairly easy to do—when it works. Sometimes, for unexplained reasons, jailbreaking just fails. Either you'll have to keep repeating the process until it works, which gets annoying, or you'll find yourself performing a full restore pretty often.Good Jailbreak Apps are Pricey - If you don't like paying for apps on the iTunes App Store, you're going to hate paying for them on the Cydia Store.Source & Further Reading including Instructions: How to Jailbreak Your iPhone: The Always Up-to-Date Guide [iOS 8.1]