Well let me start with the music format question. Android devices will play music in any of the following formats:
|Type||Format / Codec||Encoder||Decoder||Details||Supported File Type(s) / Container Formats|
|Audio||AAC LC/LTP||•||•||Mono/Stereo content in any combination of standard bit rates up to 160 kbps and sampling rates from 8 to 48kHz||• 3GPP (.3gp)
• MPEG-4 (.mp4, .m4a)
• ADTS raw AAC (.aac, decode in Android 3.1+, encode in Android 4.0+, ADIF not supported)
• MPEG-TS (.ts, not seekable, Android 3.0+)
|HE-AACv2 (enhanced AAC+)||•|
|AMR-NB||•||•||4.75 to 12.2 kbps sampled @ 8kHz||3GPP (.3gp)|
|AMR-WB||•||•||9 rates from 6.60 kbit/s to 23.85 kbit/s sampled @ 16kHz||3GPP (.3gp)|
|Mono/Stereo (no multichannel). Sample rates up to 48 kHz (but up to 44.1 kHz is recommended on devices with 44.1 kHz output, as the 48 to 44.1 kHz downsampler does not include a low-pass filter). 16-bit recommended; no dither applied for 24-bit.||FLAC (.flac) only|
|MP3||•||Mono/Stereo 8-320Kbps constant (CBR) or variable bit-rate (VBR)||MP3 (.mp3)|
|MIDI||•||MIDI Type 0 and 1. DLS Version 1 and 2. XMF and Mobile XMF. Support for ringtone formats RTTTL/RTX, OTA, and iMelody||• Type 0 and 1 (.mid, .xmf, .mxmf)
• RTTTL/RTX (.rtttl, .rtx)
• OTA (.ota)
• iMelody (.imy)
|Vorbis||•||• Ogg (.ogg)
• Matroska (.mkv, Android 4.0+)
|PCM/WAVE||•||8- and 16-bit linear PCM (rates up to limit of hardware)||WAVE (.wav)|
Seems a bit confusing? Well right off the bat: Wave and MIDI are formats that you don’t see too much anymore. WAV is uncompressed so you end up with large file sizes and MIDI is a digital form of music that is transferred in digital form so it sounds more like an old school phone ringtone. You won’t run into either of these two much anymore… Also AMR/3GP were designed for use on 2G/3G phones, also a format that you don’t see too much.
What we have left in the list are MP3, which is the most common of formats, along with AAC, which wikipedia describes as: “Designed to be the successor of the MP3 format”. They also state that it has better sound quality at similar bitrates. Basically saying that it sounds better at a similar (or smaller) file size. So the main 2 that you are going to see are AAC and MP3.
The other 2 (OGG and FLAC) are open file formats. FLAC is a lossless format, meaning that it plays the music back without any form or modification like the popular formats do. OGG can be both a lossy and lossless, depending on the file itself. Both of these 2 are a lot less popular, mainly because the file sizes can be much larger.
My suggestion based on all this info would be to go with MP3 or AAC, just because of the availability. MP3s are really easy to make from CDs, simply download an app (or use Windows Media Player, iTunes, or AmaroK).
Downloading music is also very simple. Music purchased through a few major services (iTunes in particular) will not let you transfer your music beyond it’s devices and software. A great alternative is the Amazon MP3 app (which is either preloaded on your phone, or is a free download on the Market) which sells it’s music files in a nonprotected MP3 file, which can be transferred wherever you want.