If you're using Xamarin.iOS and are working with the Unified API (which you should be!) you may be having issues with the current SQLite NuGet packages. There's an issue that you may have already worked around, but in case you haven't and are seeing the error below when trying to install the SQLite.Net.Platform.XamarinIOS into your Xamarin.iOS project, read on.
Attempting to resolve dependency 'SQLite.Net-PCL'. Installing 'SQLite.Net.Platform.XamarinIOS 2.4.1'. Successfully installed 'SQLite.Net.Platform.XamarinIOS 2.4.1'. Adding 'SQLite.Net.Platform.XamarinIOS 2.4.1' to TemplateV1.iOS. Uninstalling 'SQLite.Net.Platform.XamarinIOS 2.4.1'. Successfully uninstalled 'SQLite.Net.Platform.XamarinIOS 2.4.1'. Install failed. Rolling back... Could not install package 'SQLite.Net.Platform.XamarinIOS 2.4.1'. You are trying to install this package into a project that targets 'Xamarin.iOS,Version=v1.0', but the package does not contain any assembly references or content files that are compatible with that framework. For more information, contact the package author.
The current package does not contain elements which are compatible with the Unified API. Your options are:
1. Go back to the Classic API
Not really an option, given the 1st of Feb deadline imposed by Apple
2. Wait for an updated NuGet package
Maybe an option, but it's cutting it fine
3. Download the source and build the binaries yourself
The source is available here: https://github.com/oysteinkrog/SQLite.Net-PCL
You'll see an already existing project for the Unified API here: https://github.com/oysteinkrog/SQLite.Net-PCL/tree/master/src/SQLite.Net.Platform.XamarinIOS.Unified
Download the repo and build SQLite.Net (Portable), followed by SQLite.Net.Platform.XamarinIOS.Unified
Take the resulting SQLite.Net.dll and SQLite.Net.Platform.XamarinIOS.Unified.dll and reference them manually in your iOS project.