Will it still sync and display in mobile?
Yes, your watchlist will still sync. The unsupported row is hidden when opened in the non-supporting app and is preserved so it displays in the platforms that support it.
Which features have different support on different platforms?
Desktop TWS supports header rows, blank rows, and more contract types (for example SLB) than mobile at this point in time. It also supports column breaks (multi-column Mosaic lists), copies of the same product in a single list, directed combos, variable tick futures (i.e. XT@SNFEASX24), and intercommodity spreads (e.g. TUT - 2y/10y TN spread). The general rule of thumb for supported Watchlist features is: Client Portal < IBKR Mobile < TWS.
Additional InformationUP