Storage space will remain unaffected between custom rom and stock they do not re-partition the device storage. But you can delete almost 300mb of bloatware from stock rom if rooted. I have 3 email accounts on my phone.. plus I call a lot of people .. 2 hours of music.. I unplug my phone around 7am and by 8pm I'm left with almost 35% charge on an average.
Current Device: Galaxy S4 I9500 (Exynos)
Running [GearCM] Optimized CyanogenMod 11.
LG Optimus G Pro
Sony Xperia Z
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