The Church in Wales published a printed lectionary every year, and you could download it as a PDF. The problem with PDFs is that there is a lot of scrolling to do once you get past the start of the year.
This new online lectionary, built and hosted by Skirrid Systems, shows the readings for today with easy navigation to the next Sunday, or to any date this century. It also includes the collects and post communion prayers for each day, and links to the readings, plus a download button to save the service details as a Word document. It is available in English and Welsh.
You can install the web page as an app on your mobile device, giving offline access to everything except readings (readings are cached offline after you open them).