Expscan Public API, use it for free.

Get Address Balance
http://expscan.info/v1/address=address

Response:

{
	"response":"success",
	"address":"0x4c9cd8f2e1a88db9df7b5afbf31540198c245395",
	"balance":"0.0001"
}
Get Info about Block
http://expscan.info/v1/block=blockNumber

Response:

{
	"response":"success",
	"miner":"0xee4fadfe332fecf44e8d52349cbc772bb651a942",
	"difficulty":"1073217536",
	"hash":"0x3a750f3e3b7de99f712a8f8665363ca273b1f8422e9b1a869bab8e7c7645f151",
	"timestamp":1442188848,
	"transactions":[]
}
Get Info about Hash
http://expscan.info/v1/hash=hashAddress

Response:

{
	"response":"success",
	"from":"0x4c9cd8f2e1a88db9df7b5afbf31540198c245395",
	"to":"0xc9710|872d3e65edbf7f8776829dd7b21f2085e40",
	"value":"1.070 EXP"
}
Get Tokens Balance on address
http://expscan.info/v1/tokenBalance=address

Response:

{
	"response":"success",
	"tokens":[{"ticker":"LAB","balance":"12530.474"},{"ticker":"PEX","balance":"110530"}]
}
Get Total Coins
http://expscan.info/v1/totalCoins

Response:

19412208