Starting yesterday (Aug 31) morning I observed some crashes in our android and ios apps. 

The apps make use of the getTicketFormsById method and depend on TicketField title fields. All TicketField title fields are null. 

Interestingly, the title fields are non-null in the web api response (api/v2/ticket_forms). 

Also note that the TicketField titleInPortal fields are non-null in the getTicketFormsById response, so this issue seems isolated to the title field. 

Was there a change yesterday to a private api?

Edits:

looks like getTicketFormsById makes use of the standard web api (/api/v2/ticket_forms/show_many.json) so this issue seems even more mysterious

I captured some sdk traffic from app for proof. i can share more of the request / response data privately if it will be useful.
"ticket_fields": [{
        "url": "https://<redacted>.zendesk.com/api/v2/ticket_fields/360030376312.json",
        "id": 360030376312,
        "type": "tagger",
        "title": null,
        "raw_title": null,
        "description": "",
        "raw_description": "",
        "position": 9999,
        "active": true,
        "required": false,
        "collapsed_for_agents": false,
        "regexp_for_validation": null,
        "title_in_portal": "Select Issue",
        "raw_title_in_portal": "Select Issue",

Looks potentially related Cloudfare cache. I added a new field to the form and when served from cache (report-to) I do not see the new field and the title fields are null as shown in partial response body above.