Firebase.

https://kodepos-2d475.firebaseio.com/

https://kodepos-2d475.firebaseio.com/list_propinsi.json?print=pretty

{
	"p1" : "Bali",
	"p10" : "Jawa Tengah",
	"p11" : "Jawa Timur",
	"p12" : "Kalimantan Barat",
	"p13" : "Kalimantan Selatan",
	"p14" : "Kalimantan Tengah",
	"p15" : "Kalimantan Timur",
	"p16" : "Kalimantan Utara",
	...
}

https://kodepos-2d475.firebaseio.com/list_kotakab/p9.json?print=pretty

{
	"k60" : "Tasikmalaya",
	"k61" : "Pangandaran",
	"k62" : "Ciamis",
	"k63" : "Banjar",
	"k64" : "Cirebon",
	"k65" : "Kuningan",
	...
}

[
	{
		"kecamatan" : "Cibiuk",
		"kelurahan" : "Majasari",
		"kodepos" : "44193"
	},
	{
		"kecamatan" : "Cibiuk",
		"kelurahan" : "Cibiuk Kidul",
		"kodepos" : "44193"
	},
	{
		"kecamatan" : "Cibiuk",
		"kelurahan" : "Cipareuan",
		"kodepos" : "44193"
	},
	...
]

A demo application built on top of Framework7.