Anonymous editing was enabled on mobile web on 30th March 2015 to all users (previous it was available in an experimental mode of the site). Now we have almost a month's worth of data I thought it would be a good time to check the impact... it's a little disappointing to be honest... but it depends what we are optimising and consider the most important.

Quick summary:
* All edits up 154%
* Edits from logged in users down 152%
* Errors up 600%
* No noticeable impact on the new active editor graph [0] (editors that hit 5 edits in the month period)
* First edits by logged in users down 176% (although this could arguably be said to  be compensated by anonymous edits)
* New account creation up by 192%

Follow ups
* Aaron H, it would be great if you could report back with some findings on the quality of the edits during this same period.
* Can anyone provide theories why registrations jumped so much? This might be related to the change or because of something else

Details on the queries I ran:
In March for a 26 day period before the change:
* 170,948 total edits [1]
* 169,845 non-anonymous edits [6]
** by 40,658 distinct users [7]
* 26,617 users completely their first ever edit [11]
* 9,528 errors [8]
* 219,012 accounts created on mobile [12]

For a similar 26 day period in April
* 263,986 total edits [2]
* 136,079 non-anonymous edits [4]
** by 26,823 distinct users [5]
* 15,109 users completely their first ever edit [10]
* 58,394 errors [9]
* 419,976 accounts created on mobile [13]

[0]  http://mobile-reportcard.wmflabs.org/
[1] select count(*) from MobileWebEditing_8599025 where event_action = 'success' and timestamp > 20150301000000 and timestamp < 20150327000000
[2] select count(*) from MobileWebEditing_8599025 where event_action = 'success' and timestamp > 20150401000000 and timestamp < 20150427000000
[3] https://phabricator.wikimedia.org/T97494
[4] select count(*) from MobileWebEditing_8599025 where event_action = 'success' and timestamp > 20150401000000 and timestamp < 20150427000000 and event_username is NOT NULL
[5] select count(distinct event_username) from MobileWebEditing_8599025 where event_action = 'success' and timestamp > 20150401000000 and timestamp < 20150427000000 and event_username is NOT NULL
[6] select count(*) from MobileWebEditing_8599025 where event_action = 'success' and timestamp > 20150301000000 and timestamp < 20150327000000 and event_username is NOT NULL
[7] select count(distinct event_username) from MobileWebEditing_8599025 where event_action = 'success' and timestamp > 20150301000000 and timestamp < 20150327000000 and event_username is NOT NULL
[8] select count(*) from MobileWebEditing_8599025 where event_action = 'error' and timestamp > 20150301000000 and timestamp < 20150327000000
[9] select count(*) from MobileWebEditing_8599025 where event_action = 'error' and timestamp > 20150401000000 and timestamp < 20150427000000
[10] select count(*) from MobileWebEditing_8599025 where event_action = 'success' and timestamp > 20150401000000 and timestamp < 20150427000000 and event_userEditCount = 0
[11] select count(*) from MobileWebEditing_8599025 where event_action = 'success' and timestamp > 20150301000000 and timestamp < 20150327000000 and event_userEditCount = 0
[12] select count(*) from ServerSideAccountCreation_5487345 where event_displayMobile = 1 and timestamp > 20150301000000 and timestamp < 20150327000000
[13] select count(*) from ServerSideAccountCreation_5487345 where event_displayMobile = 1 and timestamp > 20150401000000 and timestamp < 20150427000000