Python should I use threading
I have decided to adopt a process rather than a threaded approach to resolving this issue. The primary factor in this decision is simplicity. The second factor is whilst one of these applications will be carrying out data acquisition the other will be communicating with a modem on an ad-hoc basis (receiving calls) I don't have control over the calling application but based on my  investigations, there is the potential for a lot to go wrong. 
There are a couple of factor which may change the approach further down the line primarily the need for the two processes to interact to prevent data contention on the database. Secondly if resources (memory/disk space/cpu) become an issue (due to the size of the device) one application should give me the ability to manage these problems. 
That said the data acquisition application is already threaded. This allows the parent thread to manage the worker when exceptions arise, as the device will not be in a managed environment.
I currently have a couple of small applications < 500 lines. I am intending to eventually run them on a small LINUX ARM box. Is it better to combine these applications and use threading, or continue to have them as two separate applications?
These applications plus a very small website use a small sqlite database, though only one of the applications write everything else currently does reads. Due to constraints of the target box I am using Python 2.6.
I am using SQLite to prevent data loss over several days of use. There is no direct interaction between the two application though there is the potential for database locking issue especially during period data maintenance. Stopping these issue are a concern also the foot print of the two applications as the target devices are pretty small.