I'm starting this thread to create an index of replacement software (that replaces default apps) as well as to index some other popular app categories. Softare can come from the App Store or side-load stores requiring Jailbreak.

If anyone has any app recommendations, please let me know. I'll be including multiple apps per category for now, but will then thin it out to a maximum of 1 or 2 per category.

Apps must perform and look great. Form and function must blend and work together. No ugly apps, no bug-ridden apps.

The first four categories of "replacements" are default apps which I think need to be replaced the most of all, since Apple's provided solutions are simply underwhelming.

Replacements for Default apps:
==========================

Music Player
- $: My Artists: http://www.macstories.net/iphone/my-artists-review/
- $3: Amp Music Player: http://itunes.apple.com/us/app/amp-music-player/id372165479?mt=8

Video Player
- VLC

Camera
- $: ClearCam (haven't checked out yet)
- $: Camera Plus Pro (haven't checked out yet) - these two seem like the best of what's available though
- $: ProCamera

Map program with offline maps (with GPS support, non navigating)
- $: Galileo - you can build your own maps offline and then copy them over (slow but versatile to do)

Calculator
-

Clock/Alarm
- $: Clock Pro
- Still looking (there's a lot of garbage in this category)

Web Browser
- Mercury Web Browser

Contacts - must use the native contacts DB and sync with Address Book, Google, etc...
- $: ABContacts (this one looks the best so far - still have to download it - supports alternate phone/sms programs instead of using built-in ones)

Notes
- Evernote (I don't like the iPhone client as much as I like the desktop version)

Calendar - must sync with iCal/CalDav/Google, etc..
- Calvetica - super clean/minimalist UI, has promise, needs more updating yet though.
- miCal - looks very full featured - this is the one I'm leaning toward


New Apps
=========

Voip (SIP Support)
- Fring
- $: Bria iPhone Edition
- $: Media5 Voip
- $: WiFone
- $: SessionTalk SIP

SMS / MMS - over data connection
- $: Messagey (US and Canada only supposedly - works by sending over email, so it doesn't work well sending to Rogers or Fido customers in Canada)
- $: Messenger for Google Voice
- SMS GV Extension - jailbreak hack to use built-in Message app through Google Voice

Visual Voice Mail
- $: Visible Voice Mail - works with any VM system that can send messages to email address

Digital Wallet (passwords/cards/banking, etc.)
- 1Password

Bluetooth File Transfer
-

GPS Navigation (turn by turn software - maps must be fully offline)
- TomTom - looks/works great so far
- Navigon - looks/works great so far

Document scanning (must support integration with other services)
- JotNot Scanner Pro: http://www.appolicious.com/finance/apps/47331-jotnot-scanner-pro-mobitech-3000-llc
- Readdle Scanner Pro

Reference
- $: AllofWiki - download offline copy of WikiPedia
- $: Oxford Deluxe English Dictionary 2nd Edition
- $: Audubon field guides for wildlife - I wish they covered more than North America

Local music streaming
- $: Squeezecast - stream music from your Squeezebox Server (turns iPhone into a Squeezebox)
- $: iPeng - Squeezebox controller/browser - can also be used to control Squeezecast (ideal)

Sketching/Drawing
- Adobe Ideas
- $: Sketchbook Mobile
- $: Layers
- $: miniDraw Plus

Photo editing/manipulation
- $: Photogene (so far it's the only one I've found worth adding to wishlist)

Unit conversion
- $: Convert

Shopping lists and comparisons
- CompareMe - price/unit/volume price shopping comparison tool
- $: Grocery Gadget - advanced grocery list app
- ShopShop - simple/basic list app

Tip calculator
- $: Tipulator

Sound/audio utilities
- SoundHoud -(supposed to also include a player) identify music by audio sampling or humming: http://itunes.apple.com/us/app/soundhound/id355554941?mt=8

Shipping/receiving
- $: Deliveries - great little app for keeping track of packages, supports a lot of mail/courier co's.


Services or Service Enhancements:
==============================

Improved Syncing
- WiFi Sync: http://www.getwifisync.com/

Locate/lock/spy lost/stolen iPhone:
- iLocalis (Jailbreak - 5euro per year): http://ilocalis.com/index.php

Filesystem access
- Netatalk (Jailbreak) - allows browsing iPhone filesystem from the desktop as a drive
- iFile - file browser for on-iPhone use
- OpenSSH - allows SSH/SFTP access TO your iPhone

Themes and UI modification - these are all Jailbreak
- Winterboard - the base framework/control panel for all UI mods
- SBSettings - quickly access common settings like enable/disable data, etc. (use the SBMatte theme with this)
- LockInfo - modify and add information to the lock screen (needs to be skinned for best look)
- Five Icon Dock - show 5 icons in the dock instead of 4
- Five Icon Switcher - set the number of icons in the task switcher