I do not know about Tainan specifically, but you can purchase the LG G2 in Taiwan.
It's just LG's naming convention. It originally derived from the LG Optimus G and LG Optimus G Pro, which were the phone's predecessors. The "Optimus" branding was removed from the G2 going forward.
Not sure about other parts of the world, but the LG G2 is releasing in the US market in all the major carriers come mid-September 2013.
MetroPCS does not carry the LG G2. However, you can use the unlocked version or the T-Mobile branded version as MetroPCS merged with them in May 2013.
The only way to fix a security error is to flash your LG G2 back to stock. Depending on what route you take, you can use a flash tool used by some developers, download the stock image and DLL file, the appropriate drivers for the LG G2 (depending on carrier), and use that flash tool to reinstall the phone's stock OS and drivers.
Check the related link section for a guide.
The LG G2 has a 9.5 star rating overall, where the Motorola has a 8.5. But for personal choices it depends on what the primary use will be.
It depends on your needs, your budget, and if you care about specs. The Samsung Galaxy S4 is much closer to the LG G2's specs than the Galaxy S3, but the S3 is still a solid smartphone to have on a budget.
It could mean that you're not getting reception where you are at. Or, there could be a carrier issue.
If you are trading just for the purpose of a larger screen and expandable storage, on the surface it might be a fair trade. However, if you get down to specs, the LG G2 has better specs (and that includes the display) than the Galaxy Mega 6.3. Besides a higher resolution display, the LG G2 has a better rear camera (13 megapixels vs. the Mega's 8 megapixels), better front camera, faster CPU and GPU, longer battery life (due to the smaller display), weighs lighter, built in FM radio, unique button placement, and a cleaner UI (Sense vs. the Mega's TouchWiz).
No
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