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Homemade Cell Phone Call Blocker?
G)-(ostly asks: "Recently, I've been plagued by a number of calls that were mis-dialed to my cell phone. They're particularly annoying because, being on a cell phone, the wrong number calls follow me everywhere as opposed to just being ignored in an empty house during the day. Verizon, of course, has scripted their drones to claim they can't do anything about it except change the number (or we can turn off the phone), which of course probably wouldn't change anything since we'd just get different mis-dials. However, since it's in my possession, would it be possible to build a software package that could be used to 'screen' unwanted numbers right on the phone? If so, how would one even begin to find APIs for phones, or load the software, once built, onto it?" How long do you figure it will take phone makers to recognize the need for this feature?
A cheap and dirty way to do this would be to add the numbers you wish to block to your phone's contact list and give them a silent ring. However, you then waste the phones memory with a phone-book entry (which can be hundreds of bytes), when all you really need is a list consisting of 10-12 digit numbers (depending on locality). The other drawback to this method is that you might need to use those contact slots, so it isn't a solution for everyone. Still, this sounds like a useful feature, but there is still the issue of how much control the cell phone's OS will give you over its basic operations (blocking messages sent from a specific number, for example). Has anyone tried doing this on their phone? What kind of luck did you have?
My old as crap sony ericsson t237 from cingular has a call management feature that lets me select groups to accept calls from. I can select to accept calls from the list, from all, or from none. Why cant you just put all the people you are most commonly expecting calls from in the "whitelist" and select to accept calls only from the list? Any other calls are directed to voicemail, where you can choose to ignore or reply at your leisure. Another benefit of this is that your voicemail message will convey who you are to the caller, and simple misdials will realize and most likely hangup. I do not see what the big deal is? What am I missing?
I'm a little tea pot.
"A cheap and dirty way to do this would be to add the numbers you wish to block to your phone's contact list and give them a silent ring. However, you then waste the phones memory with a phone-book entry (which can be hundreds of bytes),..."
Hundreds of bytes? Spare me the drama. If you're the type of person with the wherewithal to even think about developing a number-blocking app for your phone, then you probably have the type of phone where hundreds of bytes isn't going to matter. What you call a "cheap and dirty" solution I'd call "cheap and simple." My "cheap" referring to less use of my time thinking about the problem.
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I used to have someone doing this all the time and so added them to my phone book as 'wrong number #1' and just not answering it. Do you really have more than the 250 or so numbers that your sim card can hold ( or more if you're using phone memory? ) An alternative would be to have caller groups and only having it ring if it was a known number, but then you have to know everyone who calls you. If they're calling from a Private Number then you're really screwed.
I once had a cell phone where I would get at least four wrong numbers per day. I'd never had that much trouble before, and never again after I changed numbers. Everyone calling was asking for a different person, so it wasn't because I had a number similar to a popular business (though that happened to me once before too).
Eventually I figured out the reason for the many wrong numbers: my exchange matched a nearby area code, and the first three digits of the rest of my number were an exchange within that area code. So, for example, let's say my number was 555 1234, there were a thousand valid numbers in the format 1 (555) 123 4###. What that meant was that anytime someone in my area code forgot to dial 1 when dialing one of those 1000 numbers, it resulted in a wrong number to me.
Once I figured that out, I got my number changed and things got much better. Don't know if that's what's happening to you, but I thought I'd mention it. If you think it is something like this, be sure to change exchanges too, not just the last four digits. Make sure the exchange does not match a nearby area code.
Cheers.
My favorite feature is the ability to assign any number that I don't want to answer again a permanent busy signal. That, BTW, includes *any* call with a blocked caller ID. I get a little kick out of seeing in my log some low-life telemarketing company trying unsuccessfully to reach me hundreds of times. I can also set timers to go directly to voicemail during certain hours (like when I want to sleep), and I can selectively filter important callers (like my family) to ring through anyway.
Costs about $15/month. Oh, yes, I can also use the VOIP phone as originally intended, too.
Nowadays, with local number portability, the 'captive' part is less of a problem, but the other features make keeping a VOIP service worthwhile.
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One checksum digit would eliminate *every* one-digit-wrong misdialed number. Why why why don't phone numbers have checksum digits?
A misdial looks exactly like an intentional dial to the phone company. There is no way that you or the phone company can prevent someone from dialing your number.
Your phone already supports basic white list or blacklist functionality. If the same people keep misdialing your number, then you'll want to blacklist them using the method sugested in the editorial portion of this article.
If, however, you get misdials from different phone numbers then you'll need to add everyone to your phone book that you want to know about immediately, and set the general ring to silent. In this way you'll still get voicemail if the caller left a message (typically misdials won't leave voice mail if you set up your outgoing message well) so you won't be completely out of the loop with a real caller from an unfamiliar phone number.
I don't see how custom software will solve this any better than the phone book will. You have four different scenarios:
1) Someone who does want to talk to you dials correctly and reaches you
2) Someone who does NOT want to talk to you dials correctly and doesn't reach you
3) Someone who does want to talk to you misdials and doesn't reach you
4) Someone who does NOT want to talk to you misdials and reaches you
Only calls from #1 and #4 reach you. There are two further possibilities:
A) The person calls from a number in your phone book
B) The person calls from a number not in your phone book (or is blocked)
A person who does want to talk to you and is not in your phone book (payphone, friend's phone, etc) looks exactly like a person who does not want to talk to you and is not in your phone book. Therefore, as far as the phone company, your phone, and any possible software you could invent knows, 1B == 4B.
Therefore the problem cannot be solved any better than it is right now with the built in phone's whitelist and blacklist. Either you will only accept calls from those you've programmed, shoving everyone else to voice mail, or you will accept calls from anyone who does not match a set of frequent misdiallers.
In the old days before caller ID one could purchase an answering machine that would not allow the home phones to ring unless the caller pressed a sequence of touchtone keys. You may be able to make software do that, but generally those devices failed in the marketplace because it was too much hassle.
Of course, this doesn't answer your question. I suppose what I'm trying to accomplish here is to ask you a question:
What does your proposed software do that your phone and/or phone company cannot already do? Are you simply suggesting an easier to maintain or more explicit blacklist/whitelist, or do you have a novel method that actually does what I suggest is impossible given the information the phone is provided? If so, getting the software onto the phone is trivial once you've convinced a few key people that what you've invented actually works.
-Adam
Actually, in some countries, like Belgium, you don't pay to receive calls, only the caller pays to talk on the phone and you also don't pay to receive text messages...
In other countries, like the US, you pay for calling and for receiving calls, and for sending and receiving text messages...
Just FYI