The following Android apps are unpublished, but are available on request:

BlueNavtex1

If you are technical enough to be able to hang a serial (conventional) bluetooth adaptor on to a NasaMarine serial output Navtex receiver, even an old one, then this android app will accept a download wirelessly and display Navtex messages on tablet or phone in the same format as BlueNavtex2 and BlueNavtex3..

The app has all its functions working (December 2020), but needs a bit of optimisation. Email me if you are interested in checking this out. I am happy to advise on bluetooth adaptor connection. There are settings and download  transmisson speeds you would need to know.

BlueNavtex3

This is now (as at November 2020) a complete and publishable android app.  It is a development of BlueNavtex2, but with the added feature of being able to download all the messages from the Nasa Marine BT3 to a stored table, so you can review them later. The downside is the download time (3 to 5 minutes). If you want this, email me. If people like it and there is a demand, I may publish it, possibly at a small premium.

Navtex Companion

This a complete and functional android app. It lists all the Navtex stations I can find on the internet by NavArea, along with the Message Type codes, and the standard broadcast time allocation table.

I doubt the data will ever be fully up to date, but I can update it at intervals if users email me verifiable changes. I have now completed version 2 of the app which has the facility of downloading an updated table from my website. You can download the .apk file here with my compliments, but once you have checked it out, please let me know if you think it is useful to you.

SerialNavtex

If you have one of the older pre-Bluetooth versions of Nasa Marine's Navtex engines with a serial output for a laptop, you can now access it from your Android tablet or smartphone. To do this you will need a USB serial adaptor containing a genuine Prolific chipset and a special USB-C or micro-USB connector ("RTG"). You may already have  a compatible serial adaptor, and the RTG is a couple of pounds on the internet. To use this app, you connect your tablet to the Navtex engine and download the messages - 30 seconds. You can then disconnect and review the messages offline, wherever you are. The app also allows you to set the channel and channel timers, and filter the messages to your preferences. Your android device needs to support the USB host function. Most do these days.  SerialNavtex image