There are more issues than the file format.
Some web sites are incompatible with our phones. I can't tell which is the issue here but for compatible sites the native system works.
Remember that Android is still the new thing on the block. Not everything works. There are folk that can't accept that and will have to bang their head a little longer.
Not to mention a few folk bought tablets instead of a laptop and then learned first hand why I said to get a laptop.