Being a programmer poor college student, I can't justify investing in Max for Live. However, it turns out that Lemur's own built-in script engine is sufficient for building a full step sequencer! It works by actually outputting MIDI note messages based on the configuration of a pad grid and MIDI time information from a DAW.
This is still an early version. I will be buying an iPad 3 when it comes out, and once I have some time to use and debug it on that I'll upload it to the Liine User Library. Until then, here's the version that I've been testing on my iPhone.
http://liine.net/en/community/user-library/view/214/
If you try it out, I'd be happy to take any suggestions for improvement. Bugs, UI quirks, new feature requests are all welcome.
Important note: If you use this sequencer through a wireless router, especially one that has a lot of other network traffic going on, you'll probably get a lot of latency and hiccups. DEFINITELY use either USB or Ad-hoc wireless for MIDI.
Setup
Make sure that your synth or DAW is sending MIDI time updates to Lemur! In Live, that means MIDI sync should be enabled. Otherwise the sequencer will just sit there and do nothing.
If you want to change what MIDI channel the sequencer outputs on, you can use the menu in the lower right of the screen.
Controls
At the top of the screen, you'll see two rows of buttons. Each pair corresponds to a measure in the sequence. The top button selects which measure you're looking at in the grid, and the bottom button is the measure enabler. The sequencer will automatically move from one measure to the next enabled measure, looping around to the beginning when it's finished.
To the left of those two rows, there's a button labeled "C". This is the copy button. Select the measure you wish to copy. Then hold the button, and press the measure you want to paste to. The sequence will be duplicated to the new measure. (Protip: Slide your finger across a range of measures while holding the copy button to paste to all of them. This makes laying a base rhythm or melody super easy.)
Below that is the grid. Each column corresponds to a sixteenth note in 4/4 time. Each row corresponds to a note. You can select what note the sequencer starts on in the upper right of the screen. The default is C1.
To the right of the sequencer grid is the velocity levels. Each slider sets the velocity that that the corresponding note will be played at.
Just above the velocity sliders, and to the right of the measure panel, is the auto-scroll button. When this is enabled, the grid will automatically follow whatever measure is currently being played.
Finally, at the very bottom of the screen there's a dark red bar. This bar sets where the end of the measure is. For 3/4 time, for example, set it just before the 4th beat in the sequence.
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