The Rdio API only gives keys for track listings through the API.
Given, say, a call to Rdio's getAlbumsForArtist method with an artist key, you might get a response similar to:
{
"status": "ok",
"result": [
{
"baseIcon": "album/a/8/2/000000000001e28a/1/square-200.jpg",
"releaseDate": "2007-07-10",
"artistUrl": "/artist/Justice/",
"duration": 2858,
"isClean": false,
"shortUrl": "http://rd.io/x/Qj5Dvck/",
"canStream": true,
"embedUrl": "https://rd.io/e/Qj5Dvck/",
"type": "a",
"price": "None",
"key": "a123530",
"icon": "http://img00.cdn2-rdio.com/album/a/8/2/000000000001e28a/1/square-200.jpg",
"canSample": true,
"name": "Justice",
"isExplicit": false,
"artist": "Justice",
"url": "/artist/Justice/album/Justice/",
"artistKey": "r80653",
"length": 12,
"trackKeys": [
"t1555455",
"t1555488",
"t1555527",
"t1555555",
"t1555583",
"t1555618",
"t1555640",
"t1555663",
"t1555693",
"t1555727",
"t1555762",
"t1555798"
],
"canTether": true,
"displayDate": "Jul 10, 2007"
},
{
"baseIcon": "album/f/2/d/0000000000451d2f/1/square-200.jpg",
"releaseDate": "2014-05-26",
Sadly, that only gets you the keys for each track.
What's the best way to get — in one request — titles (and other associated information, if possible) for the tracks of a given album?
What you're looking for is the use of the extras field. I'm kind of surprised that album pages doesn't list it, but there's a "tracks" extra. It'll add a 'tracks' array to your result that has all the basic track information in it (which includes "name").