Stop The Camera From Going In And Out Of Focus
Check the top middle of the app for the letters "AF" standing for "Auto Focus".
If the icon is highlighted, then Auto Focus is enabled. Tap the icon to turn Auto Focus off. To manually focus the picture, cue a source in the preview pane, and tap the part of the image you want to emphasize.
You can also open the "Camera Control" menu and toggle ON the "Disable Auto Focus When Live" setting. This will negate the AF setting for the angle that is shown in the Preview window while the source is Live. Using this, you could have an Angle on Auto Focus while it is cued up, but switch to Manual Focus automatically when the source goes Live.