iModSign allows iOS app bundles (.ipa) files to be signed or resigned with digital certificate from Apple for distribution.
This is a very easy to use tool.

Requirements:

Mac OS 10.5+

Got a Windows PC? Heres How To Use iModSign On Windows! – http://tinyurl.com/6yjxpnl
(Guide is designed for iReSign but just make sure to download iModSign after its installed)

A certificate issued by Apple – Which can be obtained at http://iMZDL.com/udid2

An .ipa file which you want to sign (Cracked App) – can be found on http://apptrackr.org

Note: Xcode is not required.

Note: This works on any iOS Device on any firmware.

Instructions on how to use iModSign:

Download iModSign on http://iMZDL.com

Register Your UDID with a Provisioning Profile & Certificate – To Use iModSign!

Open all the files that were emailed to you.
AppleWWDRCA.cer – Open with keychain under login.
developer_identity.cer – Open with keychain under login.
Certificates.p12 – Open with keychain, password for this file is provided in the email.
Development.mobileprovision – Email the mobile provision to yourself, open up your email in mail app and install it.

Having issues installing the provision profile on your device? Then try dragging the mobile provision into iTunes while the device is plugged in.
Still having issues installing the provision profile on your device? Then you need Xcode, download Xcode for your Mac OS and install it then open the mobile provision. Plug your device in. Take the mobile provision in Xcode and drag it to your device.

Open iModSign

You will be brought to a screen asking you to choose the certificate, if your certificate is in keychain it will show up. Select the certificate and click use this certificate.

Drag the .iPA into where it says “Drag .IPA Here” or browse for IPA file, Note: You can drag as many as you want, even browse and add an entire folder full.

You can view the setting by clicking settings, there are numerous stuff you can add to make your iModSign experience easier and better.

Click Start Job!

Done! The app is now resigned all you need to do it drag the resigned copy of the iPA into iTunes (if you didn’t check the option to do it automatically) and Sync!

Boom! Syncing should now work perfectly!

Any Questions? Read http://iMZDL.com/faq2