For Application Development is bitcoind RPC the Only Way?
You have many options but Bitcoind is a popular one due to its initial ease.


Use Bitcoind
Use an API such as Coinbase or Blockchain.info be careful as these can be slow and not as secure.
Use one of the many libraries made for various languages. Bitcoinj for Java, Libbitcoin for C++, Gocoin for Golang, and for other languages like Python and Javascript you can always find tools in a github search. This is the search for Python libraries in python.