Novena Software

Enigmail
Enigmail (and possibly some other Thudnerbird extensions) explicitly only works for x86 and x64, Linux, Windows, and Darwin. You need to modify install.rdf. If you're using Debian, it's called Icedove.

&lt;em:targetPlatform>Linux_arm-eabi-gcc3&lt;/em:targetPlatform>
 * Install the extension, either from Thunderbird itself, or through "apt-get install enigmail"
 * Edit either ~/.thunderbird/*.default/extensions/{GUID}/install.rdf OR /usr/lib/xul-ext/enigmail/install.rdf
 * Find the lines that contain &lt;em:targetPlatform> (e.g. &lt;em:targetPlatform>Darwin_x86_64-gcc3&lt;/em:targetPlatform>)
 * Add the following line:
 * Save and close the file
 * Restart Thunderbird

PulseAudio
PulseAudio uses a type of scheduling that requires very accurate DMA response. Unfortunately, this is not accurate with the current i.MX6 DMA driver. The workaround is to use time-based scheduling instead.

load-module module-udev-detect tsched=0
 * Edit /etc/pulse/default.pa
 * Locate the line that says "load-module module-udev-detect"
 * Replace it with the following line:
 * Save the file
 * Run "killall pulseaudio"

Chromium
You can install chromium (aka chrome browser) by cherry picking it out of the ubuntu armhf builds: https://launchpad.net/ubuntu/trusty/armhf/chromium-browser

You may need to manually satisfy some dependencies (eg libgcrypt11 was pulled out of jessie but needed as of chromium 47.0.2526.73).

Chromium is much faster than iceweasel on Novena for browsing the web.