Android vendors are probably having a good day today, as two separate research reports indicate dominance in both the smartphone and tablet sectors for the second quarter of 2013.Kantar Worldpanel ComTech gave its read on the U.S. smartphone marketplace, indicating that Android held 51.5% of smartphone sales from April-June.But there may be a few clouds on the horizon for Android: iOS sales were at 42.5% of sales, up 3.3% from the same time last year. Even Windows had some upward mobility, with a 4% smartphone sales share, up 1.1% from 2012.Meanwhile, Strategy Analytics released its global tablet market report for the same quarter, which showed that Android shipped on 34.6 million tablets this past quarter, which was 67.0% of the total 51.7 million units shipped.Apple shipped 14.6 million tablets in the same period, which was 28.3% of the global tablet sales. Windows operating system tablets shipped 2.3 million units (4.5%).The growth of tablet shipments was the most notable part of the report. In the second quarter of 2012, there were a total of 36.1 million tablets sold, just 1.5 million more than the number of Android-loaded tablets alone that shipped in 2Q 2013. In all, tablets shipments year-over-year grew 43%.