Well. I work for the U.S. Dept. of Commerce Export Assistance Center. First up, your personal ipad is considered baggage. You don't declare it. Purchased ipad's for someone else are another story entirely. You need to be VERY careful taking technology outside the US. An ipad could well be a device that requires a validated export license. Even if the device doesn't, the software might. AND, the US not only restricts what products you can sell where, it also restricts to specific people. Go to www.bis.doc.gov for information. Penalties for export violations are SEVERE. Fines and jail times. Do your homework or hire a shipping company.
As far as taxes. The U.S. does not levy an export tax. The Philippines will have an import duty along with other taxes, likely a VAT. Check www.buyusa.gov/philippines/en/ for info.
Hope this helps.