Dogecoin (DOGE) was founded in the US in 2013 as a joke but quickly gained a large following. It became a popular cryptocurrency (DOGE) used for tipping the content creators (mainly on Reddit and Telegram). As the creators had no serious plans for their currency they didn't elaborate a roadmap and were not working on the improvement of their project too much. The founder of Dogecoin Jackson Palmer left the project in 2015.
DigitalNote (XDN) cryptocurrency is currently listed on the number of exchanges against cryptos (BTC or ETH). It emerged in 2015 as a Fair Launch, which did not imply any reward for developers, ICO campaign or premined blocks . Recently, XDN held a swap to the XDN 2.0 network with improved functionality.