CBL view differences between IOS and Android

Mobile
1

I have a basic view in CBL. The map function looks like this:

accounts_by_userid_view: {
  "map": function(doc) {
    if (doc.type === 'account') {
      emit(doc.user_id, null);
    }
  }.toString()
}

An android, after making an update to a document in the view I notice that there are 2 versions indexed in the view. I believe in IOS the only version is the latest version of the doc. Is this expected?

FYI The content of the view after the update is this, notice 2 entries for document 1009643f57f453132900e1e476b64aa0, one at rev 26, and the other at 27:

{
  total_rows: 0,
  offset: 0,
  rows: [
    {
      doc: {
        authorised_instances: [
          '38c3acb5-5a93-4102-8bd5-128da28102df'
        ],
        _rev: '20-cfc322efb1acd02abab0c153e0c780d1',
        verified_contact_methods: [
          'other.testaccount@snowmonkey.co.uk'
        ],
        archived_chat_groups: [],
        _id: 'b424b402b574e4402d55b1d0511db309',
        view_preferences: {
          left_handed_view: false
        },
        owner: '3900241d-b43b-489f-84b1-c884c14a9d7a',
        type: 'account',
        emails: [],
        user_id: '3900241d-b43b-489f-84b1-c884c14a9d7a',
        friends: [
          'ff39116b-5197-420c-8223-73284e4d1b65'
        ]
      },
      id: 'b424b402b574e4402d55b1d0511db309',
      key: '3900241d-b43b-489f-84b1-c884c14a9d7a',
      value: null
    },
    {
      doc: {
        authorised_instances: [
          '6246c834-19da-4e93-a8a7-a9f4bb0d715d'
        ],
        _rev: '27-2b9e4f925ef64c842336139f51079e4f',
        verified_contact_methods: [
          'testersonbob@gmail.com'
        ],
        archived_chat_groups: [],
        _id: '1009643f57f453132900e1e476b64aa0',
        emails: [],
        type: 'account',
        owner: 'ff39116b-5197-420c-8223-73284e4d1b65',
        view_preferences: {
          left_handed_view: false
        },
        friends: [
          '3900241d-b43b-489f-84b1-c884c14a9d7a'
        ],
        user_id: 'ff39116b-5197-420c-8223-73284e4d1b65'
      },
      id: '1009643f57f453132900e1e476b64aa0',
      key: 'ff39116b-5197-420c-8223-73284e4d1b65',
      value: null
    },
    {
      doc: {
        authorised_instances: [
          '6246c834-19da-4e93-a8a7-a9f4bb0d715d'
        ],
        _rev: '26-511e5f516709e143dea2543bd98315ca',
        verified_contact_methods: [
          'testersonbob@gmail.com'
        ],
        archived_chat_groups: [],
        _id: '1009643f57f453132900e1e476b64aa0',
        view_preferences: {
          left_handed_view: true
        },
        owner: 'ff39116b-5197-420c-8223-73284e4d1b65',
        type: 'account',
        emails: [],
        user_id: 'ff39116b-5197-420c-8223-73284e4d1b65',
        friends: [
          '3900241d-b43b-489f-84b1-c884c14a9d7a'
        ]
      },
      id: '1009643f57f453132900e1e476b64aa0',
      key: 'ff39116b-5197-420c-8223-73284e4d1b65',
      value: null
    }
  ]
}

Here’s another example:

2

Can anyone help? Having differences in the view behaviour is causing me real problems. Looks like in android all revisions are being stored in the view, where as in IOS only the latest version is.