The optimization process and recommendations:

1. Avoid Selecting Unnecessary Columns (query line: 2): Avoid selecting all columns with the '*' wildcard, unless you intend to use them all. Selecting redundant columns may result in unnecessary performance degradation.
2. Avoid Subselect When Selecting MAX/MIN Per Group (query line: 14): Constant subquery results are usually not cached by the database, especially in non-recent database versions. Therefore, a constant subquery in a WHERE clause will be fully evaluated for every row the WHERE clause will examine, which can significantly impact query performance. Use the method mentioned in the example instead.
3. Create Optimal Indexes (modified query below): The recommended indexes are an integral part of this optimization effort and should be created before testing the execution duration of the optimized query.

Optimal indexes for this query:

CREATE INDEX devices_idx_notify_userid_ostype ON Devices (Notify,UserId,OSType);
CREATE INDEX trackerlocations_idx_receivedtime_trackerid ON TrackerLocations (ReceivedTime,TrackerId);
CREATE INDEX trackers_idx_trackerid ON Trackers (TrackerId);

The optimized query:

SELECT
        tl.*,
        d.* 
    FROM
        TrackerLocations AS TrackerLocations1 
    INNER JOIN
        Trackers t 
            ON TrackerLocations1.TrackerId = t.TrackerId 
    INNER JOIN
        Devices d 
            ON t.UserId = d.UserId 
    LEFT JOIN
        TrackerLocations AS TrackerLocations2 
            ON (
                TrackerLocations2.TrackerId = TrackerLocations1.TrackerId
            ) 
            AND (
                TrackerLocations1.ReceivedTime < TrackerLocations2.ReceivedTime
            ) 
    WHERE
        (
            1 = 1 
            AND TrackerLocations1.ReceivedTime >= DATEADD(MINUTE, -2, GETUTCDATE()) 
            AND d.OSType <> 3 
            AND d.Notify = 1
        ) 
        AND (
            TrackerLocations2.ReceivedTime IS NULL
        )