You can go for Windows Phone 8X undoubtedly when you want to choose between Windows 8X and iPhone 4. The reasons are
1. Windows 8X has plenty more battery power
2. Significantly faster CPU clock speed
3. Somewhat higher pixel density
4. Has branded damage resistant glass
5. Considerably more megapixel (photo, front camera)
6. DlNA certified
7. Has NFC
8. Provision of wireless charging
9. Measurable faster uploads about 50 MBits/s
10. Has touch autofocus.
11. Very faster downloads about 100 MBits/s
12. Bigger screen size about 4.3”
Cheers!!!!!!!!