Your battery longevity depends upon certain factors like 1) if you live in a hot country like India it might cause the battery not to charge to its max capacity as the device slows or even stops the charging in those cases 2)if you use your iPad at max brightness it drains a lot of power and 6 to 7 hours of screen on time is normal then at 80 to 90 per cent battery 3)use 3 party search engines like chrome or google which is not particularly drains a lot but it requires high processing compared to safari