Voltage regulator problem
LD1777S33 has a drop out voltage of 1 - 1.1V. This cannot work with a 3.7V battery.
Qwik fix, use 2x 3.7 batteries in series
NOTE: replace R15 with 270K
Alternatives (needs PCB redisign):
MAX16904 (600mA) TSSOP
TPS63021 (2A) 3mm × 4mm 14-Pin VSON Package (DSJ)
Overengineer solution: AXP209 (QFN48) http://linux-sunxi.org/AXP209