Upcoming version of TeX Writer will adjust the assistant keyboard layout according to character usage data we collected. We'll also provide a way for you to customize your own layout. The table below is a summary of character usage from 50 LaTeX papers (randomly selected in various fields), about 80K lines in total.

• Count: Occurrences of the character;
• Taps per Char: how many taps are required to input this character on iPad's default keyboard. (In real world use case, it is possible that two adjacent characters are on the same page, so you may not need to switch at all. We didn't take that into calculation.)

                 |         |   Taps   |
          Char   |   Count | Per Char | Total Taps 
        ---------+---------+----------+------------
               \ | 109043  |    3     |  327129
               { |  50950  |    3     |  152850
               } |  50922  |    3     |  152766
               $ |  72334  |    2     |  144668
               _ |  36223  |    3     |  108669
               % |  25484  |    3     |   76452
               ) |  26333  |    2     |   52666
               ( |  26113  |    2     |   52226
               1 |  21758  |    2     |   43516
               ^ |  13856  |    3     |   41568
               - |  19031  |    2     |   38062
               , |  32289  |    1     |   32289
               . |  29524  |    1     |   29524
               = |   8786  |    3     |   26358
               2 |  11985  |    2     |   23970
               0 |  11955  |    2     |   23910
               & |   6572  |    2     |   13144
               + |   3794  |    3     |   11382
               ` |   2748  |    4     |   10992
               [ |   3603  |    3     |   10809
               ] |   3593  |    3     |   10779
               9 |   5254  |    2     |   10508
               3 |   5000  |    2     |   10000
               * |   3159  |    3     |    9477
               ' |   4143  |    2     |    8286
               : |   4027  |    2     |    8054
               5 |   3520  |    2     |    7040
               4 |   3390  |    2     |    6780
               | |   2177  |    3     |    6531
               > |   2090  |    3     |    6270
               # |   2030  |    3     |    6090
               8 |   2461  |    2     |    4922
               / |   2392  |    2     |    4784
               6 |   2377  |    2     |    4754
               ~ |   1503  |    3     |    4509
               7 |   2165  |    2     |    4330
               ; |   1800  |    2     |    3600
               @ |   1562  |    2     |    3124
               " |   1129  |    2     |    2258
               < |    655  |    3     |    1965
               ! |    786  |    2     |    1572
               ? |     78  |    2     |     156