I am a bit of a geek in my spare time and if you want something off the shelf then this won't be for you but it seems quite doable to host every thing yourself and just use your webspace to do it all - enquiries payment round management everything. Front end gui and back end for analytics etc
Anyway it seems to me that all these phone apps mentioned are just CRM (customer relationship management) type programs. They have been about for years, you can buy them or download torrents if that's your bag. there are versions for microsoft, quickbooks and sage which is brilliant because you can tie them to your accounts contacts diary and any other databases you may have so that's the office computer sorted then - may even work on windows based phones? You'll just need to spend some time setting it up for you.
Then I wondered if Google were doing one of their freebie online ones to go with all their other online software (app) which would be good for android based phones ... (unfortunately I'm a Nokia fan they make brilliant phones n900 at the mo 64gig linux based open source fast as fluff brilliant!) ... never got that far with it all but somebody probably has on one of the open source coding hubs on the net (this is where most of it originates anyway) sites like
https://github.com/ for code and better
gitorious.org/ for the gui's.
Just take the bits you want employ a coder from the Indian sub-continent for £30 (easy online) buy a server and host it all from there bit of marketing/advertising on forums and watch the money roll in while your out window cleaning.
Never got that far with it because I found the open source thing for Wordpress Joomla Drupal so it can all just be integrated into your own website and you can just use it on the fly whichever phone/computer your using (they only have a short life before a better one becomes available anyway). The back end will be maintained by the Wordpress Drupal Joomla community because of all the bloggers wanting to be on different platforms. Lots of work to do on it but nothing ventured nothing gained and it'll be like my little project if anyone is interested in being a bit geeky let me know how you get on maybe it'll be fantastic maybe crap
Cutting a long story short the link is
http://civicrm.org/ and you'll probably need to start reading up on some php/mysql
I use George on a Palm m130 by the way and by the time you've waded through this Google will probably have free software up online in the cloud which would render this whole post useless but you did ask and it is Saturday morning missus at the shop!
Best of luck!
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