A useful tilt meter to guide you around. It is simple to find out if one surface is vertical by placing your phone on it. If the cursor figure centers in the cross-grid then the surface is aligned. The angle in degrees of the x or y axis to the vertical are shown in the bottom and left text boxes.
Tilt Meter Free v1.01 Signed Nokia S60v5/Symbian^3/Anna/Belle
Nokia Symbian^3 (S^3)
Nokia N8, C6-01, C7-00, E7-00, E6, X7, 500, 603, 700, 701, 808
Symbian S60v5 (S^1)
Nokia 5228, 5230, 5233, 5235, 5250, 5530 XpressMusic, 5800 XpressMusic, C5-03, C6-00, N97, N97 mini, X6, Samsung i8910 Omnia HD, Sony Ericsson Satio, Sony Ericsson Vivaz